Full opinion text
BEEZER, Circuit Judge: Both parties appeal from the district court’s order granting permanent injunc-tive relief against California prison officials. Although this appeal presents a variety of discrete issues, the case presents this general issue: Does the protection afforded by the United States Constitution require that San Quentin and Folsom prison officials remain subject to controls imposed by the district court or should prison control be returned to California prison officials? We conclude that, in general, the district court assumed too much control over the day to day affairs of the prisons. Therefore, constitutional restraints require modification of the district court’s decree. I BACKGROUND This class action was commenced on behalf of prisoners committed to administrative segregation in four California prisons: San Quentin, Folsom, Deuel Vocational Institute at Tracy, and the Correctional Training Facility at Soledad. The defendants are the Director of the California Department of Corrections and the wardens of the prisons involved. We address orders pertaining to San Quentin and Folsom. The complaint was filed in 1973. In the first phase of the proceedings, a three-judge district court held that the state’s practice of removing prisoners from the general population and placing them in maximum security segregation units violated the prisoners’ fourteenth amendment right to due process of law. See Wright v. Enomoto, 462 F.Supp. 397 (N.D.Cal.1976) (hereinafter referred to as “Wright I”). In Wright I, the defendants were ordered to employ a variety of procedures before segregating prisoners for administrative reasons. See id. at 404-05. The Supreme Court summarily affirmed the district court. Enomoto v. Wright, 434 U.S. 1052, 98 S.Ct. 1223, 55 L.Ed.2d 756 (1978). In the next phase of the litigation, the district court issued an unpublished comprehensive preliminary injunction governing the conditions of confinement in the segregation units of the four prisons. We reversed the district court and vacated the injunction on the grounds that the district court applied the incorrect legal standard in assessing the plaintiffs’ eighth amendment claims. See Wright v. Rushen, 642 F.2d 1129 (9th Cir.1981). On remand, the district reevaluated the conditions of confinement under the standard prescribed by Wright v. Rushen and issued a detailed preliminary injunction governing conditions of confinement and procedures for placement and retention in administrative segregation. See Toussaint v. Rushen, 553 F.Supp. 1365 (N.D.Cal. 1983). Although we affirmed the district court for the most part, we vacated a portion of the order which was not supported by the record. Toussaint v. Yockey, 722 F.2d 1490 (9th Cir.1984). We also directed the district court to reconsider its conclusions regarding the continuing propriety of procedural requirements in light of the Supreme Court’s decision in Hewitt v. Helms, 459 U.S. 460, 103 S.Ct. 864, 74 L.Ed.2d 675 (1983). See Toussaint v. Yockey, 722 F.2d at 1494 n. 6. In the present phase of this case, the district court entered an injunction, which we refer to as the Permanent Injunction, governing conditions of confinement and segregation procedures at San Quentin and Folsom. Toussaint v. McCarthy, 597 F.Supp. 1388 (N.D.Cal.1984). The court appointed a special master, known as the Monitor, to assist in the implementation of the Permanent Injunction and to advise the court regarding the need for further modifications of the Injunction. Id. at 1420-22. Pursuant to the order of reference, the Monitor ordered the release of a number of prisoners from administrative segregation. Defendants now challenge various aspects of the Permanent Injunction and the district court’s affirmance of the Monitor's order to release a number of prisoners from administrative segregation. Defendants urge us to vacate parts III, IV(B), (C), and (D), and to modify Parts 11(6), (10), and (15) of the Permanent Injunction. Defendants also complain about the district court’s affirmance of the Monitor’s decision to release prisoners Altamirano, Mendoza, Ramos, Castro, Gallegos, Hayes, Ferrel, Shryock, Pina, Elmore and Barela. Plaintiffs cross-appeal the district court’s refusal to extend the sweep of the injunction to cover additional prison conditions. Plaintiffs urge us to hold that enforced idleness in administrative segregation constitutes cruel and unusual punishment, that inmates legitimately barred from the prison law library be provided with adequate legal assistance, that health care services provided at Folsom do not meet minimum constitutional standards, and that denial of contact visitation constitutes cruel and unusual punishment. The opinions cited above offer additional discussion of the facts. We will discuss specific facts and arguments in turn. II SCOPE OF FEDERAL INJUNCTIVE RELIEF In Ruiz v. Estelle, 679 F.2d 1115 (5th Cir.1982), amended, 688 F.2d 266 (5th Cir.1982), cert. denied, 460 U.S. 1042, 103 S.Ct. 1438, 75 L.Ed.2d 795 (1983), the Fifth Circuit reviewed a district court’s order of injunctive relief against state prison officials. The Fifth Circuit described the role of the federal courts as follows: There is no iron curtain drawn between the Constitution and the prisons of this country. When the remedial powers of a federal court are invoked to protect the constitutional rights of inmates, the court may not take a hands-off approach. The duty to protect inmates’ constitutional rights, however, does not confer the power to manage prisons, for which courts are ill-equipped, or the capacity to second-guess prison administrators. Federal courts should not, in the name of the Constitution, become enmeshed in the minutiae of prison operations. Our task is limited to enforcing constitutional standards and does not embrace superintending prison administration. 679 F.2d at 1126 (notes and quotations omitted). The court also stated that As a matter of respect for the state’s role and for the allocation of functions in our federal system, as well as comity toward the state, the relief ordered by federal courts must be consistent with the policy of minimum intrusion into the affairs of state prison administration that the Supreme Court has articulated for the federal courts. “[T]he principles of federalism which play such an important part in governing the relationship between federal courts and state governments” are applicable “where injunctive relief is sought ... against those in charge of an executive branch of an agency of state” government. [Rizzo v. Goode, 423 U.S. 362, 380, 96 S.Ct. 598, 608, 46 L.Ed.2d 561 (1976).] We should, therefore, fashion the least intrusive remedy that will still be effective. In shaping that remedy, we must also, as a matter of judicial administration, regard the essential nature of federal courts in an adversary system. Our remedial powers are inherently judicial, not administrative. 679 F.2d at 1145 (notes and quotations omitted). We agree with the Fifth Circuit’s description of the role of the federal courts. Injunctive relief against a state agency or official must be no broader than necessary to remedy the constitutional violation. See Milliken v. Bradley, 433 U.S. 267, 280, 97 S.Ct. 2749, 2757, 53 L.Ed.2d 745 (1977) (remedy must be related to condition alleged to offend the constitution); Swann v. Charlotte-Mecklenburg Board of Education, 402 U.S. 1, 16, 91 S.Ct. 1267, 1276, 28 L.Ed.2d 554 (1971) (task is to correct, by a balancing of the interests, the condition that offends the constitution; judicial powers may be exercised only on the basis of a constitutional violation); Hoptowit v. Spellman, 753 F.2d 779, 785 (9th Cir.1985) (judge must order correction of specific violations and may require only that these corrections bring the conditions above constitutional minima); Newman v. Alabama, 683 F.2d 1312, 1319 (5th Cir.1982) (relief must be no broader than necessary to remedy the constitutional violation), cert. denied, 460 U.S. 1083, 103 S.Ct. 1773, 76 L.Ed.2d 346 (1983); Hoptowit v. Ray, 682 F.2d 1237, 1246 (9th Cir.1982) (function of court is limited to determining whether a constitutional violation has occurred and to fashioning a remedy that does no more and no less than correct that particular constitutional violation); Ruiz v. Estelle, 679 F.2d at 1144-46 (court must fashion the least intrusive remedy that will still be effective). A federal court may not enjoin a state official to follow state law. Pennhurst State School and Hospital v. Halderman, 465 U.S. 89, 97-121, 104 S.Ct. 900, 906-19, 79 L.Ed.2d 67 (1984). “The federal courts do not sit to supervise state prisons, the administration of which is of acute interest to the States.” Meachum v. Fano, 427 U.S. 215, 229, 96 S.Ct. 2532, 2540, 49 L.Ed.2d 451 (1976). In fashioning a remedy for constitutional violations, a federal court must order effective relief. Smith v. Sullivan, 611 F.2d 1039, 1044 (5th Cir.1980). Therefore, a federal court may order relief that the Constitution would not of its own force initially require if such relief is necessary to remedy a constitutional violation. See North Carolina State Board of Education v. Swann, 402 U.S. 43, 46, 91 S.Ct. 1284, 1286, 28 L.Ed.2d 586 (1971); Swann v. Charlotte-Mecklenburg Board of Education, 402 U.S. at 15-16, 91 S.Ct. at 1276. A defendant’s history of noncompliance with prior court orders is a relevant factor in determining the necessary scope of an effective remedy. Hutto v. Finney, 437 U.S. 678, 687, 98 S.Ct. 2565, 2571, 57 L.Ed.2d 522 (1978); Hoptowit v. Ray, 682 F.2d at 1247; Ruiz v. Estelle, 679 F.2d at 1155-56. However, our goal is to cure only constitutional violations. Swann v. Charlotte-Mecklenburg Board of Education, 402 U.S. at 16, 91 S.Ct. at 1276; Wright v. Rushen, 642 F.2d 1129, 1133-34 (9th Cir.1981). The commission of a federal judge is not a “general assignment to go about doing good.” Jett v. Castaneda, 578 F.2d 842, 845 (9th Cir.1978). Accordingly, in-junctive restraints that exceed constitutional minima must be narrowly tailored to prevent repetition of proved constitutional violations, and must not intrude unnecessarily on state functions. Ruiz v. Estelle, 679 F.2d at 1156. See generally Mishkin, Federal Courts as State Reformers, 35 Wash. & Lee L.Rev. 949 (1978). Ill SCOPE OF APPELLATE REVIEW We are guided by three standards of review. We defer to the district court’s findings of fact unless they are clearly erroneous. Anderson v. City of Bessemer, 470 U.S. 564, 105 S.Ct. 1504, 1510-11, 84 L.Ed.2d 518 (1985); Fed.R.Civ.P. 52(a). We review the district court’s legal conclusions de novo. In re McLinn, 739 F.2d 1395, 1398 (9th Cir.1984) (en banc); United States v. McConney, 728 F.2d 1195, 1201 (9th Cir.) (en banc), cert. denied, 469 U.S. 824, 105 S.Ct. 101, 83 L.Ed.2d 46 (1984). We review the scope of injunctive relief for an abuse of discretion. Hutto v. Finney, 437 U.S. at 687-88, 98 S.Ct. at 2572; Swann v. Charlotte-Mecklenburg Board of Education, 402 U.S. at 15, 91 S.Ct. at 1275-76; Hoptowit v. Ray, 682 F.2d at 1245-46. The term, “abuse of discretion,” is often misunderstood and, perhaps, is an unfortunate label. See Pearson v. Dennison, 353 F.2d 24, 28 n. 6 (9th Cir.1965); R. Aldisert, The Judicial Process 759 (1976). Yet, the legacy of hundreds of cases renders “abuse of discretion” a term of art. See Friendly, Indiscretion About Discretion, 31 Emory L.J. 747, 762-63 (1982). We must recognize, however, that the term is a “verbal coat of many colors.” Id. at 763 (quoting United States v. L.A. Tucker Truck Lines, 344 U.S. 33, 39, 73 S.Ct. 67, 70, 97 L.Ed. 54 (1952) (Frankfurter, J., dissenting)). Judge Friendly notes that [t]here are half a dozen different definitions of “abuse of discretion,” ranging from ones that would require the appellate court to come close to finding that the trial court had taken leave of its senses to others which differ from the definition of error by only the slightest nuance, with numerous variations between the extremes. Friendly, supra, at 763. The Third Circuit has reasoned that [i]n our judicial system, a wide variety of decisions covering a broad range of subject matters, both procedural and substantive, is left to the discretion of the trial court. The justifications for committing decisions to the discretion of the court are not uniform, and may vary with the specific type of decisions. Although the standard of review in such instances is generally framed as “abuse of discretion,” in fact the scope of review will be directly related to the reason why that category or type of decision is committed to the trial court’s discretion in the first instance. United States v. Criden, 648 F.2d 814, 817 (3d Cir.1981) (footnote omitted). We agree with Criden. The extent of our deference to the district court is determined by several competing factors. The remedy prescribed by the district court is something more than a mere permanent injunction. We address a “structural injunction” in which a United States district court has enjoined state administrative officials in order to force a state agency to comply with constitutional standards. Such an injunction presents several relevant considerations, some of which militate towards great deference, and others which demand close and exacting scrutiny. In protracted, complex litigation, the district court will acquire a close familiarity with the facts, parties, and nuances of the case, especially, as is the situation here, when the same judge has presided throughout. See Hinkle, Appellate Supervision of Remedies in Public Law Adjudication, 4 Fla.St.U.L.Rev. 411, 440 (1976). The ability to hear witnesses and directly view prison conditions places the district court judge in a superior position to consider alternative forms of relief. A district court’s ability to fashion the most effective remedy may be hampered by unnecessary appellate interference. However, the choice of remedy in structural litigation also involves several factors weighing in favor of close appellate review. First, the very familiarity that allows a district court to design an effective remedy may lead to excessive involvement and a breakdown of institutional perspective. See Fiss, The Social and Political Foundations of Adjudication, 6 Law & Human Behav. 121, 126 (1982). The court of appeals, which enjoys greater distance from the daily affairs of the litigation, is in a better position to assure detached neutrality. See Hinkle, supra, at 441. Second, structural litigation frequently involves a close association of rights and remedies. See Note, Complex Enforcement: Unconstitutional Prison Conditions, 94 Harv.L.Rev. 626, 637-40 (1981). As we have noted above, the scope of federal injunctive relief against an agency of state government must be narrowly tailored to enforce constitutional requirements only. The adoption of a remedy in a particular case tends to establish the norm that defines the future standard of conduct. The precedential value of the adoption of a particular remedy raises questions of consistency and authoritativeness that can be resolved similarly to resolution of legal questions. Third, and perhaps most importantly, a federal district court’s exercise of discretion to enjoin state political bodies raises serious questions regarding the legitimacy of its authority. See Fletcher, The Discretionary Constitution: Institutional Remedies and Judicial Legitimacy, 91 Yale L.J. 635, 642-44 (1982). Other than appellate review, few effective external controls check the district court’s power. Our weighing of the above factors leads us to the following standard of review. We will scrutinize the injunction closely to make sure that the remedy protects the plaintiffs’ constitutional rights and does not require more of state officials than is necessary to assure their compliance with the constitution. Within these parameters, we will defer to the district court. IV THE EXISTENCE OF A LIBERTY INTEREST The fourteenth amendment provides that no state shall “deprive any person of life, liberty, or property without due process of law ...” U.S. Const, amend. XIV, § 1; see Hewitt v. Helms, 459 U.S. at 466, 103 S.Ct. at 868. Our threshold inquiry, therefore, is whether plaintiffs have a liberty interest in remaining in the general population. If plaintiffs do not possess a liberty interest, the constitution does not require prison officials to accord plaintiffs any procedural protections when deciding to segregate plaintiffs for administrative reasons. See Meachum v. Fano, 427 U.S. 215, 96 S.Ct. 2532, 49 L.Ed.2d 451 (1976). A liberty interest may arise from either of two sources: the due process clause itself or state law. Hewitt, 459 U.S. at 466, 103 S.Ct. at 868. In Wright I, the district court held that California prisoners possessed liberty interests on both grounds. First, the court held that the due process clause itself prohibits arbitrary placement of prisoners in administrative segregation. The court reasoned that: When a prisoner is transferred from the general prison population to the grossly more onerous conditions of maximum security, be it for disciplinary or for administrative reasons, there is a severe impairment of the residuum of liberty which he retains as a prisoner — an impairment which triggers the requirement for due process safeguards. 462 F.Supp. at 402. Second, the court held that section 3330 of Chapter 4, Article 6 of the Rules and Regulations of the Director of Corrections constituted a state-created liberty interest. The district court assumed that the Wright I decision was law of the case in these proceedings. 597 F.Supp. at 1416. Plaintiffs, similarly, contend that we are bound by Wright I, especially in light of the Supreme Court’s summary affirmance. A. Law of the Case The doctrine of law of the case was “crafted with the course of ordinary litigation in mind. Such litigation proceeds through preliminary stages, generally matures at trial, and produces a judgment, to which after appeal, the binding finality of res judicata and collateral estoppel will attach.” Arizona v. California, 460 U.S. 605, 618-19, 103 S.Ct. 1382, 1391, 75 L.Ed.2d 318 (1983). Here, however, we review a structural injunction, which involves the ongoing application of changing law to changing circumstances. Because permanent injunctive relief controls future conduct, we are sensitive to the need for modification when circumstances change. A continuing decree of injunction directed to events to come is subject always to adaptation as events may shape the need. The distinction is between restraints that give protection to rights fully accrued upon facts so nearly permanent as to be substantially impervious to change, and those that involve the supervision of changing conduct or conditions and are thus provisional and tentative.... [A] court does not abdicate its power to revoke or modify its mandate if satisfied that what it has been doing has been turned through changing circumstances into an instrument of wrong. United States v. Swift & Co., 286 U.S. 106, 114-15, 52 S.Ct. 460, 462, 76 L.Ed. 999 (1932) (citations omitted). A change in the law may constitute a changing circumstance requiring the modification of an injunction. System Federation No. 91 v. Wright, 364 U.S. 642, 647-48, 81 S.Ct. 368, 371, 5 L.Ed.2d 349 (1961). An intervening judicial opinion may require modification of an injunction. See Pasadena City Board of Education v. Spangler, 427 U.S. 424, 437-38, 96 S.Ct. 2697, 2705, 49 L.Ed.2d 599 (1976) (when intervening clarification of constitutional law reduced obligations of state officials, district court abused its discretion by refusing to modify injunction accordingly). “When a change in the law authorizes what had previously been forbidden, it is an abuse of discretion for a court to refuse to modify an injunction founded on superseded law.” American Horse Protection Association v. Watt, 694 F.2d 1310, 1316 (D.C.Cir.1982). The Fourth Circuit’s decision in Nelson v. Collins, 659 F.2d 420 (4th Cir.1981), is closely analogous to the instant case. In Nelson, the district court found “double celling” of inmates to be cruel and unusual punishment and ordered the prison administration to cease double celling. Id. at 421. The Fourth Circuit affirmed the district court’s legal conclusions but remanded with instructions to fashion a decree that incorporated defendants’ timetable for elimination of overcrowding. Id.; see Johnson v. Levine, 588 F.2d 1378 (4th Cir.1978) (en banc). The district court modified its decree accordingly. See 659 F.2d at 421 (procedural background of case). When defendants realized that they could not comply with prescribed timetables, they moved to modify the injunction. See id. at 423. In April of 1981, the district court denied the motion, found defendants in civil contempt, and imposed sanctions. See id. Defendants appealed. Id. On June 15, 1981, the Supreme Court decided Rhodes v. Chapman, 452 U.S. 337, 101 S.Ct. 2392, 69 L.Ed.2d 59 (1981), which held, in short, that double celling does not violate the eighth amendment. The Fourth Circuit vacated the district court’s order disapproving double celling. See 659 F.2d at 429. The Fourth Circuit also vacated the civil contempt citation and imposition of sanctions. Id. The Fourth Circuit reasoned that “[t]he question for purposes of decision here becomes, therefore, whether there have been, since the entry of the original Decree in these cases, changes in either operative facts or laws which cast a new light upon the facts or law as originally ruled on in these cases.” Id. at 424. The Nelson court found that Rhodes v. Chapman, and Bell v. Wolfish, 441 U.S. 520, 99 S.Ct. 1861, 60 L.Ed.2d 447 (1979), mandated a different result from that reached by the court sitting en banc. 659 F.2d at 424-29. The Eleventh Circuit’s opinion in Newman v. Graddick, 740 F.2d 1513 (11th Cir.1984), similarly demonstrates that structural injunctive relief must follow the changing contours of constitutional law. In Newman, the district court ordered prison administrators to show cause why they should not be held in contempt for violating prior orders of the court concerning the Alabama state prison system. Id. at 1519. The district court also ordered that prisoners be released from confinement to relieve overcrowding. Id. The Eleventh Circuit vacated the order. Id. at 1522. The court held that “total compliance with a prior judgment or consent decree is not required before a court can entertain a request for modification.” Id. at 1519-20. The Eleventh Circuit further held that the Supreme Court’s intervening decision in Rhodes v. Chapman, along with changed factual circumstances, required reconsideration of the propriety of injunctive relief. Id. at 1521. Similarly, we cannot rely on Wright I. Neither premise upon which the Wright I court relied in finding a liberty interest still exists. In Hewitt v. Helms, the Supreme court held that the due process clause does not of its own force create a liberty interest in freedom from administrative segregation. It is plain that the transfer of an inmate to less amenable and more restrictive quarters for nonpunitive reasons is well within the terms of confinement ordinarily contemplated by a prison sentence.... Accordingly, administrative segregation is the sort of confinement that inmates should reasonably anticipate receiving at some point in their incarceration. Hewitt, 459 U.S. at 468, 103 S.Ct. at 869. A liberty interest does not arise even when administrative segregation imposes “severe hardships,” such as “denial of access to vocational, educational, recreational, and rehabilitative programs, restrictions on exercise, and confinement to [one’s] cell for lengthy periods of time.” See id. at 467 n. 4, 103 S.Ct. at 869 n. 4; Clark v. Brewer, 776 F.2d 226, 228-30 (8th Cir.1985) (due process clause itself does not create liberty interest notwithstanding the fact that conditions in “close management” are significantly more harsh than conditions in general population); see also McFarland v. Cassady, 779 F.2d 1426, 1427-28 (9th Cir.1986) (Supreme Court in Hewitt held that due process clause does not give inmate liberty interest in remaining in general population). Therefore, the Wright I court’s holding that the due process clause creates a liberty interest in remaining in the general population is no longer correct. The Wright I court’s reliance on section 3330 is entitled to no deference. The version of section 3330 upon which the Wright I court relied has been repealed. See 15 Cal.Admin.Code § 3330 (former section 3330 was repealed on April 18, 1980). A state-created liberty interest exists only as long as the statute or regulation creating it remains effective. If the state repeals the statute or eliminates the regulation, the liberty interest ceases to exist. Clark v. Brewer, 776 F.2d at 232. The Wright I liberty interest determinations, therefore, neither guide nor control our consideration today. Therefore, the doctrine of law of the case does not preclude review of the continuing propriety of permanent injunctive relief. The relevant question becomes whether intervening changes in law or fact require different results. B. Eighth Amendment Liberty Interest Plaintiffs argue that the existence of eighth amendment violations in the administrative segregation units raises a due process liberty interest. We disagree. Plaintiffs’ sole authority for this proposition is a footnote from Justice Stevens’ dissenting opinion in Hewitt v. Helm. We find this a curious use of authority. Not only is the sole authority a footnote from a dissenting opinion, but the footnote does not support plaintiffs’ position. Justice Stevens indicated that if such eighth amendment violations existed, “the Constitution would impose substantive, rather than procedural limits on transfers into segregated status.” 459 U.S. at 481 n. 4, 103 S.Ct. at 876 n. 4 (emphasis added). Some fundamental considerations support Justice Stevens’ conclusion. The state has no right to subject a prisoner to cruel and unusual punishment. The eighth amendment is not a “maybe” or a “sometimes” proposition. If conditions violate the eighth amendment, all prisoners have the right to be free of such conditions. The right does not vary depending on the threat that the individual prisoner presents to institutional security. No amount of process can justify subjecting a prisoner to cruel and unusual punishment. Moreover, acceptance of such an argument would create an unworkable standard. The assumption implicit in plaintiffs’ argument is that eighth amendment violations exist in the segregation unit but do not exist in the general population. If both locations were infected with eighth amendment violations, process would be a meaningless gesture; it would make no sense to interpose a constitutional impediment to transfer from one place to another when the conditions in both locations are constitutionally impermissible. Assuming arguendo that the conditions in the general population lacked significant • eighth amendment violations, we would have to determine what quantum of violation in administrative segregation would be sufficient to create an eighth amendment liberty interest. Wright v. Rushen, 642 F.2d at 1133-35, counsels that we consider separately each condition that allegedly contributes to the violation of plaintiffs’ eighth amendment rights; a variety of discrete conditions exist in the segregation units. If we were to find that the defendants cured one of the conditions, would the eighth amendment liberty interest evaporate? Or if we were to find that a particular condition in the general population violated the eighth amendment, would the liberty interest vanish? Or perhaps plaintiffs would have us hold that a prisoner has an interest in remaining with his own eighth amendment violation and not being subjected to another in its place. Plaintiffs’ approach would require a comprehensive determination regarding the conditions throughout the prison, if not the entire state prison system, to determine whether the eighth amendment created a due process liberty interest. We decline to require such an ambitious task in the name of such a dubious proposition. The presence of eighth amendment violations in the segregation units, therefore, does not create a liberty interest. We will not parlay one constitutional right into another. C. State-Created Liberty Interest Several cases decided after the Supreme Court affirmed the district court’s decision in Wñght I illuminate our perspective on state-created liberty interests. Before we will recognize a constitutionally protected liberty interest, state law must direct that a given action will be taken or avoided only on the existence or nonexistence of specified substantive predicates. See Olim v. Wakinekona, 461 U.S. 238, 249, 103 S.Ct. 1741, 1747, 75 L.Ed.2d 813 (1983); Hewitt v. Helms, 459 U.S. 460, 470-72, 103 S.Ct. 864, 870-71, 74 L.Ed.2d 675 (1983); Greenholtz v. Inmates of the Nebraska Penal and Correctional Complex, 442 U.S. 1, 11-12, 99 S.Ct. 2100, 2106, 60 L.Ed.2d 668 (1979); Meachum v. Fano, 427 U.S. 215, 226-27, 96 S.Ct. 2532, 2539, 49 L.Ed.2d 451 (1976); Allen v. Board of Pardons, 792 F.2d 1404 (1986); Roberts v. Spalding, 783 F.2d 867, 870 (9th Cir.1986); McFarland v. Cassady, 779 F.2d 1426, 1428 (9th Cir.1986); Rizzo v. Dawson, 778 F.2d 527, 530 (9th Cir.1985); Baumann v. Arizona Department of Corrections, 754 F.2d 841, 844 (9th Cir.1985). [14] The adoption of guidelines to structure the exercise of discretion does not necessarily create a liberty interest. Roberts v. Spalding, 783 F.2d at 870; Baumann v. Arizona Department of Corrections, 754 F.2d at 844. As the Supreme Court has stated, The creation of procedural guidelines to channel the decision-making of prison officials is, in the view of many experts in the field, a salutory development. It would be ironic to hold that when a state embarks on such desirable experimentation it thereby opens the door to scrutiny by the federal court, while states that choose not to adopt such procedural provisions entirely avoid the strictures of the Due Process Clause. The adoption of such procedural guidelines, without more, suggests that it is these restrictions alone, and not those federal courts might also impose under the Fourteenth Amendment, that the state chose to require. Hewitt v. Helms, 459 U.S. at 471, 103 S.Ct. at 871. 1) The California Statutory Sentence Credit Scheme The district court held that California Penal Code sections 2931 through 2933 create a liberty interest in sentence reducing credits. 597 F.Supp. at 1416-17. In a nutshell, sections 2931 and 2933 create a two-tiered scheme: Penal Code section 2933 provides that a state prison inmate may receive six months of worktime credit for every six months of full-time performance in a credit qualifying work, training or education program established by the Director of Corrections. Prisoners willing to participate in a full-time credit qualifying assignment, but who either are not assigned to such a program, or are assigned for less than full time, are to earn credits under the formula provided for by Penal Code section 2931, which is a four-month combined work and good behavior credit for each eight months served. People v. Vallardes, 162 Cal.App.3d 312, 320, 208 Cal.Rptr. 604, 608 (1984). Examination of section 2933 leads to the conclusion that prisoners have no right to earn the one-for-one worktime credits provided by that section. Section 2933 provides that “[w]orktime credit is a privilege, not a right.” Cal.Penal Code § 2933(b). Section 2933 expressly contemplates that not all prisoners will be assigned to a credit qualifying program. See Cal-Penal Code § 2933(a) (“ ... every prisoner willing to participate in a full-time credit qualifying assignment but who is either not assigned to full-time assignment or is assigned to a program for less than full time, shall receive no less credit than is provided under section 2931”). Although the California legislature intended the worktime sentence reducing scheme to instill a work ethic, see People v. Vallardes, 162 Cal.App.3d at 321, 208 Cal.Rptr. at 609, it did not create an absolute right to participate in work programs; the legislature created only a “reasonable opportunity.” See CabPenal Code § 2933(b). Moreover, a prisoner’s “reasonable opportunity to participate” must be “consistent with institutional security and available resources.” See CabPenal Code § 2933(b). Section 2933 delegates broad authority to the Director of Corrections to allocate worktime resources between various categories of prisoners. See, e.g., In re Barnes, 176 Cal.App.3d 235, 221 Cal.Rptr. 415, 416-17 (1985) (Department of Corrections has established priority list; segregation unit prisoners are at bottom of list). Prisoners are not entitled automatically to participate in worktime credit programs. People v. Rosaia, 157 Cal.App.3d 832, 848, 203 Cal.Rptr. 856, 867 (1984). There is no guarantee that work programs will be available. People v. Caruso, 161 Cal.App.3d 13, 16 n. 5, 207 Cal.Rptr. 221, 224 n. 5 (1984). In sum, section 2933 merely creates a possibility of early release; it does not create a constitutionally protected liberty interest. See Greenholtz v. Inmates of the Nebraska Penal and Correctional Complex, 442 U.S. 1, 8-11, 99 S.Ct. 2100, 2104-05, 60 L.Ed.2d 668 (1979). Therefore, we conclude that section 2933 does not create a liberty interest in one-for-one worktime credits. This conclusion, however, does not address the question of whether section 2933 creates a liberty interest in the one-for-two goodtime credits provided by section 2931. Section 2931 applies by its own terms to prisoners who are incarcerated for crimes committed prior to January 1, 1983 and who have not waived the right to receive credits under section 2931. Cal.Penal Code §§ 2931(d), 2934; see In re Ramirez, 39 Cal.3d 931, 933, 705 P.2d 897, 899, 218 Cal.Rptr. 324, 325-26 (1985), cert. denied, — U.S. —, 106 S.Ct. 2266, 90 L.Ed.2d 711 (1986). More importantly for our purposes, section 2933 establishes that prisoners who are willing to participate in the worktime credit scheme but who are denied the opportunity to do so through no fault of their own “shall receive no less credit than is provided under Section 2931.” CabPenal Code § 2933(a). Section 2931 provides that a prisoner’s sentence may be reduced by four months for every eight months that the prisoner serves. Three of the four months accrue automatically if the prisoner commits no illegal acts or serious disciplinary infractions. CabPenal Code § 2931(b). One of the four months is based solely on participation in “work, educational, vocational, therapeutic or other prison activities.” CabPenal Code § 2931(c). In practice, this one month credit is granted unless a prisoner refuses to accept work when offered. People v. Austin, 30 Cal.3d 155, 161-62, 636 P.2d 1, 5, 178 Cal.Rptr. 312, 316 (1981); 15 Cal.Admin.Code § 3043; Cal.Penal Code §§ 2931(c), 2932(b); see also People v. Sage, 26 Cal.3d 498, 510 n. 1, 611 P.2d 874, 880-81 n. 1, 165 Cal.Rptr. 280, 286 n. 1 (1980) (Bird, C.J., concurring and dissenting). While section 2931 differs somewhat from the Nebraska statute at issue in Greenholtz v. Inmates of the Nebraska Penal and Correctional Complex, 442 U.S. 1, 99 S.Ct. 2100, 60 L.Ed.2d 668 (1979), in all material respects it is identical. Section 2931 contains the “shall/unless” formula that we find dispositive. See Baumann v. Arizona Department of Corrections, 754 F.2d 841, 844 (9th Cir.1985). Therefore, we conclude that section 2931 creates a constitutionally protected liberty interest. The conclusion that section 2931 creates a liberty interest, however, does not assist plaintiffs in this case. Since the defendants generally grant the credit to segregated prisoners, administrative segregation does not implicate the liberty interest arising from sections 2931 and 2933. The existence of a liberty interest, therefore, is irrelevant and cannot support the district court’s holdings. 2) California Decisional Law The plaintiffs argue that “by virtue of its appellate court decisions applying its constitution, California has created a “substantial liberty interest in not being placed in lockup by arbitrary procedures.” Plaintiffs primarily rely on Conti v. Dyer, 593 F.Supp. 696 (N.D.Cal.1984). In Conti, the district court held that California state-court decisions created a liberty interest cognizable under the federal Constitution. Id. at 700-02. The Conti court found that California decisional law created a federal liberty interest notwithstanding the fact that the California courts expressly reject federal due process analysis and recognize a liberty interest in freedom from all arbitrary state action. Id. at 701; see People v. Ramirez, 25 Cal.3d 260, 268, 599 P.2d 622, 627, 158 Cal.Rptr. 316, 320 (1979) (“When an individual is subjected to the deprivatory governmental action he always has a due process liberty interest both in fair and unprejudiced decision making and in being treated with respect and dignity.”); see also Inmates of Sybil Brand Institute for Women v. County of Los Angeles, 130 Cal.App.3d 89, 108, 181 Cal.Rptr. 599, 609 (1982). The district court’s decision in Conti is not persuasive for several reasons. First, the court failed to acknowledge that the due process clause of the fourteenth amendment and the due process clause of the California constitution seek to protect qualitatively different interests. Under the fourteenth amendment, when the state deprives a person of liberty, it must provide that person with procedural protection. Mathews v. Eldridge, 424 U.S. 319, 335, 96 S.Ct. 893, 903, 47 L.Ed.2d 18 (1976). Unless a liberty interest is implicated, arbitrary state action does not violate the fourteenth amendment. Hewitt, 459 U.S. at 466-69, 103 S.Ct. at 868-70. The due process clause of the fourteenth amendment focuses in relevant part on protecting liberty. The due process clause of the California constitution also seeks to protect liberty. But in addition, the due process clause of the California constitution seeks to promote accuracy and reasonable predictability in all government decision making when individuals are subject to any deprivatory action. People v. Ramirez, 158 Cal.Rptr. at 320. The California constitution does not impose the threshold requirement that a liberty interest exist. Id. Even though the distinction between the two approaches will be academic in some instances, the distinction is critical in prisoners’ rights cases. Under federal due process analysis, a legally incarcerated prisoner is stripped of all but the most incremental interest in liberty. Hewitt, 459 U.S. at 467, 103 S.Ct. at 869; Greenholtz v. Inmates of the Nebraska Penal and Correctional Complex, 442 U.S. 1, 99 S.Ct. 2100, 60 L.Ed.2d 668 (1979). The federal perspective instructs that arbitrary decision making cannot deprive a person of that which has already been taken. Greenholtz, 442 U.S. at 8-11, 99 S.Ct. at 2104-05. The threshold inquiry, therefore, is whether the state has given back to the prisoner some liberty interest that previously the state had taken away. Stated alternatively, we must determine to what extent the state has deprived a criminal defendant of liberty in the first place. For federal purposes, the extent and nature of the prisoner’s remaining or re-created liberty is determined by looking for the substantive conditions or predicates that must exist before the state can again take the liberty away. Baumann v. Arizona Department of Corrections, 754 F.2d 841, 843-45 (9th Cir.1985). The quantity of procedural protections that a state may offer prisoners is not dispositive in determining the existence of a federal liberty interest. Greenholtz, 442 U.S. at 7, 99 S.Ct. at 2103. As the Court in Olim v. Wakinekona stated, “[a] liberty interest is of course a substantive interest of an individual; it cannot be the right to demand needless formality.” [Shango v. Jurich, 681 F.2d 1091, 1100-01 (7th Cir.1982).] Process is not an end in itself. Its constitutional purpose is to protect a substantive interest to which the individual has a legitimate claim of entitlement. 461 U.S. at 250, 103 S.Ct. at 1748 (footnote omitted). In contrast, the California due process clause requires process notwithstanding the absence of substantive predicates or conditions. People v. Ramirez, 158 Cal.Rptr. at 320. The state’s provision of additional protection is entirely permissible. But the fact that the state courts call this additional protection a liberty interest does not make it so for the purposes of the federal constitution. Although a state court’s determination of state law binds the federal courts, interpretation of the federal constitution cannot be circumscribed by state definitions. The California cases requiring heightened procedural protection, therefore, do not create a federally cognizable liberty interest. 3) California Prison Regulations The plaintiffs argue that sections 3335 and 3336 of Title 15 of the California Administrative Code create a liberty interest. These sections govern the placement and retention of prisoners in administrative segregation. Our hesitance to construe a statute or regulation as creating a liberty interest is especially great when the statute or regulation governs the day-to-day administration of a prison. Again, Hemtt instructs that The deprivations imposed in the course of daily operations of an institution are likely to be minor when compared to the release from custody at issue in parole decisions and goodtime credits. Moreover, the safe and efficient operation of a prison on a day-to-day basis has traditionally been entrusted to the expertise of prison officials_ These facts suggest that regulations structuring the authority of prison administrators may warrant treatment, for purposes of creation of entitlements to “liberty,” different from statutes and regulations in other areas. Hewitt v. Helms, 459 U.S. at 470, 103 S.Ct. at 870 (citations omitted). Accordingly, we have noted in the context of inter-institutional transfers that “[u]nless there is some guarantee that transfer will not be effected except for misbehavior or some other specified reason, due process protections cannot apply.” Rizzo v. Dawson, 778 F.2d at 530 (emphasis added). We are convinced that sections 3335 and 3336, standing alone, do not create a liberty interest. However, when read in conjunction with section 3339 of the California Administrative Code, sections 3335 and 3336 withstand our exacting scrutiny; they create a constitutionally protected liberty interest. Section 3335 specifies those circumstances requiring the immediate removal of an inmate from the general population. Nothing in section 3335 purports to limit the Department of Correction’s authority to segregate inmates to the circumstances enumerated in that section. The only mandatory language in section 3335 runs to the benefit of prisoners in the general population; they have some expectation that their dangerous neighbors will be removed to administrative segregation. Nothing in section 3335 suggests that a prisoner shall be allowed to remain in the general population absent the specified circumstances. Section 3336 contains mandatory language running to the benefit of the segregated prisoner. Specifically, section 3336 requires that a sufficiently senior officer make the segregation decision, that the decision be documented, that the prisoner receive assistance, if needed, in presenting his case, and that the prisoner be informed of the reason for his segregation. Sections 3335 and 3336 standing alone, therefore, constitute a procedural guideline that “channels] the decision-making of prison officials.” See Hewitt, 459 U.S. at 471, 103 S.Ct. at 871. Such procedural requirements, even if mandatory, do not raise a constitutionally cognizable liberty interest. Olim v. Wakinekona, 461 U.S. at 250, 103 S.Ct. at 1748. However, section 3339(a) provides that “[rjelease from segregation status shall occur at the earliest possible time in keeping with the circumstances and reasons for the inmate’s initial placement in administrative segregation.” 15 Cal.Admin.Code § 3339(a) (emphasis added). Section 3339(a) indicates that absent justification, a prisoner may not be retained in administrative segregation. The use of the word, shall, constitutes the mandatory language needed to create a liberty interest. See Hewitt, 459 U.S. at 471-72, 103 S.Ct. at 871. As the Supreme Court reasoned in Hewitt, the word “shall” alone is not sufficient. Rather, the liberty interest is created when the word “shall” is used to mandate certain procedures “in connection with requiring specific substantive predicates for action.” 459 U.S. at 472, 103 S.Ct. at 871 (emphasis added). Those substantive predicates are contained in section 3335, and include standards for removal from the general inmate population where there is an immediate threat to the inmate's own safety or the safety of others, or when institutional security is endangered or the integrity of an investigation put in jeopardy. These standards are incorporated into section 3339 by that section’s reference to “the circumstances and reasons for the inmate’s initial placement in administrative segregation.” We think, therefore, that the word “shall,” read in conjunction with these specific substantive predicates, does create a liberty interest in the present case. We note, moreover, that the word “shall” is not used simply to mandate an investigation but to mandate immediate release, absent procedures that determine that the substantive predicates for retaining the inmate in restrictive custody are demonstrated. V PROCEDURAL REQUIREMENTS GOVERNING PLACEMENT AND RETENTION IN ADMINISTRATIVE SEGREGATION A. PLACEMENT Our conclusion that the state has created a liberty interest in freedom from administrative segregation requires us to determine the quantum of process required by the fourteenth amendment. The determination of what process is due generally requires consideration of three distinct factors: First, the private interest that will be affected by the official action; second, the risk of an erroneous deprivation of such interest through the procedures used, and the probable value, if any, of additional or substitute procedural safeguards; and finally, the Government’s interest, including the function involved and the fiscal and administrative burdens that the additional or substitute procedural requirement would entail. Mathews v. Eldridge, 424 U.S. 319, 335, 96 S.Ct. 893, 903, 47 L.Ed.2d 18 (1976). “It is axiomatic that due process ‘is flexible and calls for such procedural protections as the particular situation demands.’ ” Green- holtz v. Inmates of the Nebraska Penal and Correctional Complex, 442 U.S. 1, 12, 99 S.Ct. 2100, 2106, 60 L.Ed.2d 668 (1979) (quoting Morrissey v. Brewer, 408 U.S. 471, 481, 92 S.Ct. 2593, 2600, 33 L.Ed.2d 484 (1972)). The district court incorporated the procedural requirements mandated by the three-judge court in Wright I. See 597 F.Supp. at 1424. The Wright I order followed the procedures required for disciplinary confinement and denial of good time credits established in Wolff v. McDonnell, 418 U.S. 539, 94 S.Ct. 2963, 41 L.Ed.2d 935 (1974). See Wright I, 462 F.Supp. at 403-05. The district court also established additional procedural requirements. The court ordered the defendants to release a prisoner no later than twelve months after placement in administrative segregation unless that prisoner is afforded all the hearing rights that attend the initial segregation decision. 597 F.Supp. at 1424. The court also required disclosure of the identity of any person providing information to prison authorities unless disclosure would endanger the safety of the source. Id, at 1424-25. Finally, the court prohibited segregation on the basis of undisclosed information. Id. at 1425. In Hewitt v. Helms, 459 U.S. 460, 103 S.Ct. 864, 74 L.Ed.2d 675 (1983), the Supreme Court held that a lesser quantum of process is due when a prisoner is placed in administrative segregation than is required by Wolff The Court stated: We think an informal, nonadversary evi-dentiary review is sufficient both for the decision that an inmate represents a security threat and the decision to confine an inmate to administrative segregation pending completion of an investigation into misconduct charges against him. An inmate must merely receive some notice of the charges against him and an opportunity to present his views to the prison official charged with deciding whether to transfer him to administrative segregation. Ordinarily, a written statement by the inmate will accomplish this purpose, although prison administrators may find it more useful to permit oral presentations in cases where they believe a written statement would be ineffective. So long as this occurs, and the decisionmaker reviews the charges and then available evidence against the prisoner, the Due Process Clause is satisfied. 459 U.S. at 476, 103 S.Ct. at 874. The process mandated for administrative segregation under Hewitt, therefore, is substantially less than that required by Part III of the Permanent Injunction. Plaintiffs nonetheless argue that Hewitt is distinguishable and a higher quantum of process is due in the instant case. Plaintiffs argue that they have a greater private interest than did the prisoners in Hewitt, that the presence of eighth amendment violations requires heightened process, and that the defendants’ noncompliance with prior court orders requires a highly structured administrative proceeding. We disagree. We recognize that the segregation units at issue in Hewitt were modern facilities and that the segregation units at San Quentin and Folsom, in contrast, are riddled with conditions that violate the plaintiffs’ eighth amendment rights. Nevertheless, the Court in Hewitt proceeded on the premise that placement in administrative segi'egation would result in “severe hardships.” 459 U.S. at 467 n. 4, 103 S.Ct. at 869 n. 4. The hardships that a segregated prisoner in Hewitt would face included “denial of access to vocational, educational, recreational, and rehabilitative programs, restrictions on exercise, and confinement to [one’s] cell for lengthy periods of time.” Id.; see id. at 479-80 n. 1, 103 S.Ct. at 875-76 n. 1 (Stevens, J., dissenting). The distinction between the private interest at issue in Hewitt and that at issue here is not as extreme as the plaintiffs assert. In addition, the state’s interest in maintaining security in San Quentin and Folsom is at least as great, if not greater, than the state’s interest shown in Hewitt. The inmate population at San Quentin and Folsom is composed of the most violent and anti-social offenders in the California prison system. See 597 F.Supp. at 1394, 1404-05. Given the disruptive propensities of the inmate population, we are especially sensitive to the Supreme Court’s admonition that “[t]he safety of the institution’s guards and inmates is perhaps the most fundamental responsibility of the prison administration.” Hewitt, 459 U.S. at 473, 103 S.Ct. at 872. The state’s interest in maintaining safety and security weighs heavily in favor of avoiding prolonged and cumbersome administrative proceedings. Finally, the value of Wolff-type, procedures was minimal in the context of the decision to segregate a prisoner for administrative reasons. When determining whether the prisoner was guilty of misconduct, as was the case in Wolff the inquiry is essentially factual. The prison administrator seeks to determine whether the prisoner committed the alleged offense. When deciding whether administrative segregation is needed, however, the administrator relies largely on subjective factors: In assessing the seriousness of a threat to institutional security, prison administrators necessarily draw on more than specific facts surrounding a particular incident; instead, they must consider the character of the inmates confined in the institution, recent and longstanding relations between prisoners and guards, prisoners inter se, and the like. In the volatile atmosphere of a prison, an inmate easily may constitute an unacceptable threat to the safety of other prisoners and guards even if he himself has committed no misconduct; rumor, reputation, and even more imponderable factors may suffice to spark potentially disastrous incidents. The judgment of prison officials in this context, like that of those making parole decisions, turns largely on purely subjective evaluations and on predictions of future behavior; indeed, the administrators must predict not just one inmate’s future actions, as in parole, but those of an entire institution. Hewitt v. Helms, 459 U.S. at 474, 103 S.Ct. at 872-73 (citations omitted); see also Jones v. North Carolina Prisoners’ Labor Union, Inc., 433 U.S. 119, 132-33, 97 S.Ct. 2532, 2541, 53 L.Ed.2d 629 (1977); 15 Cal. Admin. Code § 3338(d), (e). A trial-like proceeding is unlikely to inform a prison administrator regarding such subjective considerations. See Clark v. Brewer, 776 F.2d at 235. We conclude that when prison officials initially determine whether a prisoner is to be segregated for administrative reasons due process only requires the following procedures: Prison officials must hold an informal nonadversary hearing within a reasonable time after the prisoner is segregated. The prison officials must inform the prisoner of the charges against the prisoner or their reasons for considering segregation. Prison officials must allow the prisoner to present his views. We specifically find that the due process clause does not require detailed written notice of charges, representation by counsel or counsel-substitute, an opportunity to present witnesses, or a written decision describing the reasons for placing the prisoner in administrative segregation. Cf. Wright I, 462 F.Supp. at 404-05; Toussaint III, 597 F.Supp. at 1424. We also find that due process does not require disclosure of the identity of any person providing information leading to the placement of a prisoner in administrative segregation. Cf. Toussaint III, 597 F.Supp. at 1424-25. B. RETENTION In Part 111(B)(1) of the Permanent Injunction, the district court ordered defendants to release prisoners from administrative segregation on the prisoner’s Minimum Eligible Release Date or at the expiration of twelve months of consecutive confinement, whichever is shorter, unless the defendants afford the prisoner all the hearing rights that attend initial placement in segregation. In Hewitt, the Supreme Court instructed that administrative segregation— may not be used as a pretext for indefinite commitment of an inmate. Prison officials must engage in some sort of periodic review of the confinement of such inmates. This review will not necessarily require that prison officials permit the submission of any additional evidence or statements. The decision whether a prisoner remains a security risk will be based on facts relating to a particular prisoner — which will have been ascertained when determining to confine the inmate to administrative segregation — and on the official’s general knowledge of prison conditions and tensions, which are singularly unsuited for “proof” in any highly structured manner. Likewise, the decision to continue confinement of an inmate pending investigation of misconduct charges depends upon circumstances that prison officials will be aware of — most typically, the progress of the investigation. Hewitt, 459 U.S. at 477 n. 9, 103 S.Ct. at 874 n. 9. The Third Circuit, similarly, has stated “the governmental interest involved in a good faith decision to subject a prisoner to administrative segregation may fluctuate with the passage of time and change of circumstances.” Mims v. Shapp, 744 F.2d 946, 953 (3d Cir.1984). In Mims v. Shapp, the Third Circuit found that monthly review of a prisoner’s status satisfied due process concerns. 744 F.2d at 952. Similarly, in Clark v. Brewer, the Eighth Circuit held that review every seven days for the first two months of segregation followed by regular review hearings every thirty days thereafter satisfied due process requirements. 776 F.2d at 234. Here, however, segregation may continue without review for as long as twelve months. We do not believe that annual review sufficiently protects plaintiffs’ liberty interest. However, we intimate no view as to the frequency of periodic review required. That is for the parties to recommend and the district court to decide in the first instance. VI SUBSTANTIVE CRITERIA GOVERNING PLACEMENT AND RETENTION IN ADMINISTRATIVE SEGREGATION In Parts III(B) and IV(B) of the Permanent Injunction, the district court imposed criteria governing placement and retention of prisoners in administrative segregation. See 597 F.Supp. at 1424, 1426. The district court required that a prisoner not be placed or retained in segregation unless allowing the prisoner to remain in the general population would severely endanger the lives of prisoners, the security of the institution, or the integrity of an investigation into suspected criminal activity or serious misconduct. Defendants argue that these criteria impose unwarranted limitations on prison management. On their face, the substantive requirements merely restate the reasons justifying administrative segregation. See 15 Cal.Admin. Code § 3335(a). In Hewitt, the Supreme Court recognized that “[t]he safety of the institution’s guards and inmates is perhaps the most fundamental responsibility of the prison administration.” 459 U.S. at 473, 103 S.Ct. at 872. The substantive requirements accommodate this concern. The Court in Hewitt also stated that administrative segregation of a prisoner “pending investigation of charges against him serves important institutional interests relating to the insulating of possible witnesses from coercion or harm.” Id. The substantive criteria accommodate the prison administration’s interests in this regard as well. Moreover, the substantive criteria apply only to placement or retention in administrative segregation. The criteria do not impinge on defendants’ ability to hold disciplinary hearings and to punish prisoners for misconduct. Since administrative segregation must not be a pretext for punitive isolation, Hewitt, 459 U.S. at 477 n. 9, 103 S.Ct. at 874 n. 9, the substantive criteria assure that plaintiffs’ due process rights are not meaningless gestures. The district court, therefore, did not abuse its discretion in fashioning these substantive criteria. VII THE INTERIM PERIOD REMEDIES In Part IV of the Permanent Injunction, the district court established an additional layer of relief to apply during the “interim period.” The court defined the interim period as that time between the date on which the Permanent Injunction issued and the date on which the Monitor certifies that defendants are “in full compliance with the Permanent Injunction and that conditions of confinement in segregation units at San Quentin and Folsom do not violate the Constitution.” 597 F.Supp. at 1425. The court ordered that any prisoner assigned to segregation could request release and, if the defendants denied the request, the prisoner could obtain review by the Monitor. The court empowered the Monitor to order the release of individual prisoners from administrative segregation. Id. at 1426. A. Habeas Corpus Jurisdiction The defendants argue that the district court lacks jurisdiction under 42 U.S.C. § 1983 to order prisoners released from administrative segregation. Defendants contend that under Preiser v. Rodriguez, 411