Full opinion text
Opinion ARABIAN,J. —This case, arising out of the 1978 death penalty law, chronicles the nocturnal massacre of a mother, father, daughter, and houseguest in the sanctity of their home, and the attempted murder of the young son, the only person to survive. A jury convicted defendant Kevin Cooper of four counts of first degree murder (Pen. Code, § 187), and one count of attempted murder with the intentional infliction of great bodily injury (§§ 664/187, 12022.7). It found true the special circumstance of multiple murder. (§ 190.2, subd. (a)(3).) Defendant had previously pleaded guilty to one count of escape from a state prison. (§ 4530, subd. (b).) After the penalty phase, the jury imposed the death penalty. The trial court denied the automatic motion to modify the verdict (§ 190.4, subd. (e)), and entered a judgment of death. This appeal is automatic. (§ 1239.) We affirm. I. Facts A. Guilt Phase The jury convicted defendant of hacking to death Douglas (Doug) and Peggy Ryen, their 10-year-old daughter Jessica, and an 11-year-old house-guest, Christopher Hughes (Chris), inside the Ryen home near the California Institute for Men (CIM), a state prison in Chino. Eight-year-old Joshua Ryen (Josh), although severely injured, survived. Two days before this execution of the innocent, defendant had escaped from CIM. 1. Prosecution Evidence a. The Crime On Saturday, June 4, 1983, the Ryens and Chris Hughes attended a barbecue at the home of George Blade in Los Serranos, a few miles from the Ryen home in Chino. Chris had received permission to spend the night with the Ryens. Between 9 and 9:30 p.m., they left the Blade residence to drive to the Ryen home. Except for Josh, they were never seen alive again. The next morning, June 5, Chris’s mother, Mary Hughes, became concerned when he did not come home. A number of telephone calls to the Ryen residence received only busy signals. Shortly after 9 a.m., Mary went to the Ryen home. On her return, she told her husband, William Hughes, that something appeared wrong because “everything was quiet up there.” After a second trip failed to reassure Mary, William went to the Ryen home to investigate. William observed the Ryen truck at the home, but not the family station wagon. Although the Ryens normally did not lock the house when they were home, it was locked on this occasion. William walked around the house trying to look inside. When he reached the sliding glass doors leading to the master bedroom, he could see inside. William saw the bodies of his son and Doug and Peggy Ryen on the bedroom floor. Josh was lying between Peggy and Chris. Only Josh appeared alive. William frantically tried to open the sliding door; in his emotional state, he pushed against the fixed portion of the doors, not the sliding door. He rushed to the kitchen door, kicked it in, and entered. As he approached the master bedroom, he found Jessica on the floor, also apparently dead. In the bedroom, William touched the body of his son. It was cold and stiff. William asked Josh who had done it. Josh appeared stunned; he tried to talk but could only make unintelligible sounds. William tried to use a telephone in the house but it did not work. He drove to a neighbor’s house seeking help. The police arrived shortly. Doug, Peggy, Chris, and Jessica were dead, the first three in the master bedroom, Jessica in the hallway leading to that bedroom. Josh was alive but in shock, suffering from an obvious neck wound. He was flown by helicopter to Loma Linda University Hospital. The victims died from numerous chopping and stabbing injuries. Doug Ryen had at least 37 separate wounds, Peggy 32, Jessica 46, and Chris 25. The chopping wounds were inflicted by a sharp, heavy object such as a hatchet or axe, the stabbing wounds by a weapon such as a knife. Jessica also had some chest wounds, probably inflicted after death by a pointed instrument such as an ice pick. Josh had fewer injuries, including wounds to the head possibly caused by a hatchet and a stab wound in the throat. Dr. Irving Root, who performed the autopsies, believed the injuries could have been inflicted quickly, within one minute for each of the victims. All of the victims had a moderate amount of food in the stomach, indicating that death probably occurred about one to three hours after they had eaten last. b. Evidence of Defendant’s Guilt Various items of circumstantial evidence connected defendant with the massacre. Defendant had been an inmate at CIM since April 29 under the name of David Trautman. On June 1, he was transferred to a minimum security portion of the prison. The next afternoon, June 2, he escaped on foot. Undisputed evidence, including fingerprints, showed that after his escape, defendant took refuge in a nearby house owned by Larry Lease and brothers Roger and Kermit Lang (hereafter the Lease house). He slept in the closet of the bedroom nearest the garage. The Lease house was the closest neighbor to the Ryen house, about 126 yards away. The window by the Lease house fireplace provided a view of the Ryen house. Kathleen Bilbia, an employee of Lease, had been living in the Lease house in May, and she had used the bedroom defendant later slept in (hereafter the Bilbia bedroom). She moved out of the house during May. By May 27, most of her belongings had been removed. On May 30 and June 1, Bilbia vacuumed and cleaned portions of the house, including the bathroom she had used (hereafter the Bilbia bathroom). Telephone records showed that two telephone calls were made from the Lease house to the Los Angeles area telephone number of Yolanda Jackson—one lasting one hundred ten minutes beginning on June 3 at 12:17 a.m., and one lasting four minutes beginning at 2:26 a.m. the same morning. Two calls were also made from that house to the Pittsburgh, Pennsylvania telephone number of Diane Williams—one lasting three minutes beginning on June 3 at 11:46 a.m., and one lasting thirty-four minutes beginning on June 4 at 7:53 p.m. This final call was only an hour or so before the Ryens and Chris Hughes left the Blade house for their unsuspected rendezvous with death. Yolanda Jackson testified that she visited defendant on May 30 at CIM. Sometime after midnight on June 3, she received a telephone call from defendant. She believed the call lasted about 30 to 45 minutes. Defendant said he had “walked out” of the prison. He asked her to help him in what Jackson believed was a “joking manner.” She refused. Defendant asked her where he should go. She said she did not know. At one point in the conversation, defendant said he was getting a cigarette. Shortly after the first conversation ended, defendant called her again. A brief second conversation ensued. The parties stipulated that if Diane Williams were called as a witness, she would testify that in June she received two telephone calls from defendant at her Pittsburgh number. Defendant told her that he had been released from prison because of a new law that had been passed, and that he needed money. She said she could not get any. He said he would call back. Defendant called Williams again the next day, and asked if she had gotten any money. She replied that she had not. On June 6, Williams received a collect call from defendant in Tijuana, Mexico. On June 4, around 10 or 11 a.m., Virginia Lang visited the Lease house briefly to get a sweater. She noticed nothing out of the ordinary. After the murders, a bloodstained khaki green button was found on the rug in the Bilbia bedroom. It was identical in appearance to buttons on field jackets inmates wore at CIM, including one defendant was seen wearing shortly before his escape. The blood on the button could have come from defendant or one of the victims. A bloodstained rope was found in the Bilbia bedroom closet. It was similar, but not identical, to a length of bloodstained rope found on the driveway of the Ryen residence. A criminalist from the San Bernardino County sheriff’s crime laboratory sprayed various areas of the Lease house with luminol, a substance used to detect the presence of blood not visible to the naked eye. A positive reaction consisting of an even “glow” ranging from about two feet to five feet above the floor was obtained on the shower walls in the Bilbia bathroom. Defendant left his footprint on the sill of this shower. There were also four positive reactions to the luminol on the rug in the hallway leading to the Bilbia bedroom that appeared to be foot impressions. Other positive reactions were obtained in the bedroom closet and bathroom sink. The reactions did not prove the presence of blood, but were “an indication that it could be blood.” Investigators found matted hair in the bathroom sink trap that appeared to have been there a long time. Other hair was not matted. A microscopic examination of one of the latter revealed characteristics similar to Jessica’s head hair. A hair removed from the bathroom shower had characteristics similar to Doug Ryen’s head hair. During the afternoon of June 5, a local citizen discovered a hatchet in some weeds next to a fence on the side of a road that led from the Ryen home out of the area. The fencepost above the hatchet had a small indentation indicating that something sharp had struck it. The hatchet was covered by bloodstains; its head was covered by dried blood and human hairs. Some of the hairs were consistent with those of Doug and Jessica Ryen. Some of the blood on the hatchet head could have come from Josh. Dr. Root, who performed the autopsies, concluded that the hatchet could have inflicted the chopping wounds. Witnesses identified the hatchet as missing from the Lease house after the killing. It had been kept in a sheath by the Lease house fireplace. Bilbia recalled seeing it by the fireplace when she was cleaning the house. On June 7, the sheath for the missing hatchet was found on the floor in the Bilbia bedroom. It had not been there when Bilbia vacated the room. Some buck knives and one or more ice picks were also missing from the Lease house. These could have inflicted the remaining injuries. A strap fitting one of the missing buck knives was found on the floor by the Bilbia bedroom closet. Investigators found three significant shoe print impressions—a partial sole impression on a spa cover outside the Ryen master bedroom, a partial bloody shoe print on a sheet on the Ryen bedroom waterbed, and a nearly complete shoe print impression in the game room of the Lease house. All three appeared to come from tennis shoes. James Taylor, an inmate at CIM who played on the same prison basketball team as defendant, issued equipment to other inmates. He testified that he issued defendant a pair of P.F. Flyer tennis shoes. Three or four days before defendant was transferred to minimum security (i.e., before June 1) defendant exchanged these shoes for a pair of “Dude” Pro Ked tennis shoes. Taylor did not remember what size shoes were issued to defendant. The Stride Rite Corporation sells Pro Ked tennis shoes to the state for use in institutions such as CIM. All “Dude” tennis shoes contain the same sole pattern. The general merchandise manager for Stride Rite testified that this pattern is not found on any other shoe that the company manufactures nor, to his knowledge (which was extensive), on any other shoe. The shoes are not sold retail, but only to states and the federal government. William Baird, the manager of the San Bernardino County sheriff’s crime laboratory, compared the shoe print impressions from the Ryen and Lease houses to each other, to the type of shoes issued to defendant, and to other shoes. He concluded that the three shoe prints “all possessed a similar tread pattern, which would indicate a similar type shoe was used in each case.” They “are consistent with one another, and . . . could have been caused by the same shoe.” The pattern was similar to the “Dude” tennis shoes used at CIM, probably size 10, but possibly size 9!A. Baird searched area stores for shoes with similar sole patterns, but could find none. The defendant testified that his shoe size was between nine and ten. Baird believed that the shoes that made the three impressions were nearly new but not brand new. With one exception, all of the blood samples obtained from the Ryen house could have come from one or more of the victims. The exception is a single drop of blood found on the hallway wall opposite the master bedroom door. Daniel Gregonis, a criminalist with the San Bernardino County sheriff’s crime laboratory, examined this drop of blood by a scientific process called electrophoresis. Human blood contains various enzymes and serum proteins. The types of enzymes vary from person to person. Electrophoresis is a technique used to distinguish between enzyme types, so as to exclude or include a person as a possible donor of a blood sample. After electrophoretic testing, Gregonis concluded that the drop could not have come from any of the victims. Based upon results obtained for several enzymes, Gregonis also concluded that the drop was consistent with defendant’s blood. Results for certain other enzymes were inconclusive. Because of various characteristics, the blood had to have come from a Black person such as defendant. One of the enzymes tested is commonly called “EAP.” Gregonis initially believed the EAP of the drop of blood was type B. When he later typed defendant’s own blood, Gregonis also believed it was EAP type B. Gregonis subsequently learned that defendant’s EAP type was RB, a rare type. Gregonis had never before seen an RB type. He reexamined the photograph of the original testing of the drop of blood, but it was inconclusive as to whether it was EAP type B or RB. Gregonis testified, however, that when he tested the drop of blood, it appeared to have the same EAP type as defendant’s blood. Brian Wraxall, another expert, described the difference between types B and RB as “fairly subtle.” Before Gregonis learned of his error regarding defendant’s EAP type, he and Dr. Edward Blake, an expert employed by the defense, tested the drop further. Because of the limited amount of the remaining sample, they performed tests that they believed had the best chance of excluding defendant as a possible donor. They did not retest for EAP. The additional tests tended to include defendant as a possible donor. Only a minute amount of the blood remained after these tests. Later, after Gregonis learned of his error regarding defendant’s EAP type, he tried to test the remaining sample for EAP. Dr. Blake was again present. This final test completely consumed the sample and was inconclusive. Electrophoretic testing also established the blood on the rope found in the Bilbia bedroom closet could have come from one of the victims but not defendant. The station wagon that was missing from the Ryen house was found on a church parking lot in Long Beach. One witness testified he put a flyer on the car on Sunday morning, June 5, the morning after the killing of the Ryen family. Another saw the car on June 7. Later, the vehicle was reported to the police, who examined it for evidence. The car contained various bloodstains, including one which could have come from one or more of the victims, but not defendant. Several hairs were recovered from the vehicle. Two criminalists microscopically compared the hairs with defendant’s hair. One believed that one of the hairs probably came from a Black person, and that “there was enough similarity between . . . the hairs from Mr. Cooper and the unknown hair that I felt the unknown hair was consistent with coming from Mr. Cooper.” The second criminalist also found it was consistent with defendant’s hair. Both believed it was most likely pubic hair. Unlike fingerprint comparison, an absolute match is not possible when comparing hairs. James Taylor, the inmate who issued the Pro Ked tennis shoes to defendant at CIM, testified that he saw defendant smoke hand-rolled cigarettes using rolling paper and “Role-Rite” tobacco issued free to inmates. This tobacco is not sold retail, but only to institutions in California such as CIM. Loose tobacco was found inside a white box in the Bilbia closet, and in the Ryen car. In addition, two cigarette butts—one of a hand-rolled cigarette—were found in the Ryen car. The tobacco in the white box was identified as Role-Rite. Criminalist Craig Ogino examined visually and microscopically the two samples of the loose tobacco and the tobacco from the hand rolled cigarette. Each sample was consistent with each other and with Role-Rite tobacco. Ogino also compared them with various other tobacco samples he obtained from a tobacco store. The other tobacco samples were all different. Aubrey Evelyn, a manager with the company that manufactures Role-Rite tobacco, also testified that he had “no doubt” that the tobacco found in the Ryen car was Role-Rite. Examination of the saliva on the two cigarette butts from the Ryen car was inconclusive, but was consistent with the cigarettes having been smoked by a nonsecretor such as defendant. Some commercial cigarettes were apparently missing from the Lease house. A Viceroy cigarette butt was found in the Bilbia bedroom. Bilbia did not smoke. A six-pack of Olympia Gold beer with one can missing was found in the refrigerator of the Ryen house. One bloodstained can was hanging over the edge of a shelf. A nearly empty can of Olympia Gold beer similar in appearance to those in the Ryen refrigerator was found in a plowed horse training arena about midway between the Ryen and Lease houses. On June 9, defendant met Owen and Angelica Handy in Ensenada, Mexico. Defendant, using the name Angel Jackson, asked for work. Handy offered defendant some food and a place to stay if he would help paint their boat, the Illa Tika. Defendant agreed. After working on the boat for two days, defendant and the Handys set sail for San Francisco. They made several stops, then eventually went to Pelican Bay near Santa Barbara, where they stayed for four or five days. The Coast Guard arrested defendant at that location after he dove off the Illa Tika, swam to a dinghy, and started to row for shore. While he was with the Handys, defendant possessed several items identified as coming from the Lease house. c. Joshua Ryen's Statements Joshua Ryen did not testify at trial. Pursuant to stipulation, two taped statements made by him were played to the jury—a videotape of a December 9, 1984, interview in which he was questioned under oath by the prosecutor and defense counsel; and an audiotape of a December 1, 1983, interview with Dr. Lorna Forbes, his treating psychiatrist. Josh never identified anyone as the assailant. In the videotaped statement, Josh said that the evening before the murders, just before the family left for the Blade barbecue, three “Mexicans” came to the Ryen home looking for work. Josh had never seen them before. The family then went to the barbecue in the truck and later returned. Josh and Chris Hughes slept in sleeping bags on the floor in Josh’s bedroom. Josh’s parents slept in their bedroom, and Jessica slept in hers. At some point during the night, Josh woke up and fell asleep again. He was reawakened by a scream. Josh woke Chris up, and they walked down the hall, stopping at the laundry room. Josh saw Jessica in the hallway. He walked closer to his parents’ room, and saw a “shadow or something” by the bathroom. It was dark. Josh could not see what the shadow was or what it was doing. Josh and Chris “started getting a little scared.” Josh started to look around. The next thing he remembered was “[j]ust waking up” surrounded by the bodies of his parents. In the audiotaped interview with Dr. Forbes, Josh said he heard his mother scream. He walked into her bedroom, and saw someone by the bed “turning his back against me.” Josh “just saw his back and his hair.” After his mother stopped screaming, and Josh “saw him,” he went into the laundry room and hid behind the door. Chris went into the parents’ room, and then “was gone.” Josh then went into the bedroom and “he knocked me out.” He thought the person was a man “because women usually don’t do that sort of thing.” Josh remembered talking to a deputy sheriff named “O.C” (Hector O’Campo). He told O’Campo he thought three men had done it because “I thought it was them. And, you know, like they stopped up that night.” He did not actually see three people during the incident. 2. Defense Evidence Defendant admitted escaping from CIM, hiding out at the Lease house, and sleeping in the Bilbia bedroom, but denied committing the murders. He said that after he talked with Diane Williams the second time, he left the Lease house on foot. He did some hitchhiking, stole a purse, and eventually made his way to Mexico where he met the Handys. Defendant denied approaching the Ryen house. The defense presented evidence of other events apparently not involving defendant that might have had something to do with the killings. The defense also presented evidence of earlier statements of Josh indicating his original belief that the three Mexicans had committed the crimes. Josh never said he saw or otherwise felt the presence of more than one assailant at the time of the murders. Dr. John Thornton, a professor of forensic science at the University of California, Berkeley, criticized various aspects of the crime scene investigation. B. Penalty Phase The prosecution presented evidence that on October 8, 1982, a man stipulated to be defendant burglarized a home in Pennsylvania, assaulted a high school student who interrupted the burglary, kidnapped her, and raped her. During the incident, defendant attempted to steal one vehicle, and did steal the rape victim’s vehicle. The jury was also allowed to consider as an aggravating factor defendant’s prior conviction of two counts of burglary in Los Angeles. The defense presented several friends and relatives of defendant who testified about his good qualities and their continuing love for him. II. Discussion A. Venue Issues Defendant moved to change venue from San Bernardino County. The court granted the motion, and transferred the case to San Diego County. Defendant contends the court prejudicially erred in transferring the case to San Diego, and in denying his later motion to change venue a second time. 1. The Facts The trial court granted the change of venue from San Bernardino County because of the nature and extent of the publicity, the nature and gravity of the crime, and the status within the community of the accused and the victims. The court found the size and population of the county to be neutral factors, and expressly rejected a defense claim that political overtones were significant. The Judicial Council suggested four counties as possible new sites for the trial—Alameda, Sacramento, Los Angeles, and San Diego Counties. Defendant preferred Alameda or Sacramento County. He stated that “downtown” Los Angeles (not the rest of the county) was acceptable. He objected to San Diego. Because of the nature and extent of the publicity in Los Angeles County, the court chose not to transfer the case there absent stipulation by both parties. The district attorney refused to so stipulate. After a hearing, the court transferred the case to San Diego County. In a lengthy oral decision, the court found that although San Diego had received more publicity about the case than either Alameda or Sacramento County, and penetration of San Diego by the Los Angeles media was “inescapable,” the postpreliminary hearing publicity in San Diego was not “particularly prejudicial.” It found that trial in San Diego would be “considerably more convenient and considerably less expensive” than trial in the northern part of the state, and concluded that “[cjonsidering all of these factors, the relative convenience, hardship, costs, time, money, publicity given, the Court finds it to be in the interests of justice that the case be transferred to San Diego County.” Prior to trial, defendant moved for a second change of venue, this time out of San Diego County. The court denied the motion, finding that there had been a “falling off of publicity” in the 15 months since the crime, the publicity was generally not inflammatory, and it was not reasonably likely defendant could not get a fair trial in San Diego County. During jury selection, defendant renewed his change of venue motion based upon the jury voir dire up to that time. The court denied the motion, stating that it “was frankly impressed with the caliber of the jurors overall. I think that you’ve got a pretty good jury, Mr. Negus [defense counsel], for the defense in this case. The prosecution hasn’t got anything to go celebrate about.” The jury was thereafter selected. The defense exercised four of its twenty-six peremptory challenges in selecting the original twelve jurors, and it used three of its four challenges in selecting the alternates. 2. Change of Venue to San Diego County After a court orders a change of venue, “it shall advise the Administrative Director of the Courts of the pending transfer.” (Cal. Rules of Court, rule 842.) The director shall, “in order to expedite judicial business and equalize the work of the judges, suggest a court or courts that would not be unduly burdened by the trial of the case.” (Ibid.) Thereafter, the court shall “transfer the case to a proper court as it determines to be in the interest of justice.” (Ibid.) Four counties were named as possible trial sites—Sacramento, Alameda, Los Angeles, and San Diego Counties. Relying solely on a law review note (Note, Change of Venue in Criminal Cases: The Defendant's Right to Specify the County of Transfer (1973) 26 Stan.L.Rev. 131), defendant first contends he has the right to select which of the four will try the case. Rule 842 of the California Rules of Court, however, provides that the court, not a party, decides where to transfer the matter. Rule 842 was adopted pursuant to legislative mandate, and governs change of venue procedures in criminal actions. (§ 1038; see People v. Rich (1988) 45 Cal.3d 1036, 1075-1076 [248 Cal.Rptr. 510, 755 P.2d 960]; McGown v. Superior Court (1977) 75 Cal.App.3d 648, 653, fn. 6 [142 CaLRptr. 262].) It is consistent with the purpose behind a change of venue, which is to ensure the defendant a fair trial (Maine v. Superior Court (1968) 68 Cal.2d 375, 378 [66 Cal.Rptr. 724, 438 P.2d 372]), not to encourage forum shopping. We therefore hold that the court, not the defendant, determines where the trial shall be transferred. The defendant is entitled to a hearing prior to the transfer at which the court should consider such factual issues as the “presence or absence of prejudicial publicity” in a possible new county, and the “relative hardship involved in trying the case in various locations.” (McGown v. Superior Court, supra, 75 Cal.App.3d at pp. 652, fn. 5, 653.) The decision of where to transfer the case lies within the discretion of the court, which must consider the “interest of justice.” (Id. at pp. 652-653.) In this case, the McGown hearing was held, and the court carefully exercised its discretion. It rejected Los Angeles because of extensive publicity. Finding that San Diego could likely provide a fair trial, the court chose that county because of the relative hardship of moving the case to northern California. We perceive no abuse of discretion. Defendant relies largely on the amount of the publicity in San Diego County, claiming it had been penetrated by the Los Angeles media. Although “pretrial publicity which is not sufficient to require a change of venue from [a county] may be sufficient to persuade [a court] that the cause should not be transferred to [that county]” (McGown v. Superior Court, supra, 75 Cal.App.3d at p. 653 [italics in original, fns. omitted]), the matter still lies within the discretion of the court. Defendant’s own position at trial was inconsistent. He accepted “downtown” Los Angeles, but argued against San Diego because of its nearness to the Los Angeles media. The publicity did not deprive the court of discretion to transfer the matter to San Diego. Defendant also argues that San Diego was a possible site for a new prison, making trial there inappropriate. The court considered this factor, but found it not to be significant. Again, we perceive no abuse of discretion. Counties in which a prison may be built are not disqualified from trying crimes committed by prisoners. Defendant also argues that in a capital case, hardship should not be considered in choosing a new trial site. We disagree. Although a defendant’s right to a fair trial in a capital case, as in any case, may not be infringed, considerations of relative hardship, and the conservation of judicial resources and public funds, are important factors in deciding between various possible venue sites. (People v. Hernandez (1988) 47 Cal.3d 315, 336 [253 Cal.Rptr. 199, 763 P.2d 1289]; see also People v. Bean (1988) 46 Cal.3d 919, 939-940 [251 Cal.Rptr. 467, 760 P.2d 996] [such factors are important in deciding whether to have a joint trial of multiple counts].) The court properly considered relative nearness as a factor weighing heavily in favor of trial in San Diego. San Diego was more convenient for witnesses, attorneys, and others, including interested citizens of San Bernardino County, the county of the crime. 3. Denial of Second Change of Venue Defendant next contends that the court erred in denying his motion for a second change of venue. A change of venue must be granted when the defendant shows a reasonable likelihood that in the absence of such relief, a fair trial cannot be had. (People v. Williams (1989) 48 Cal.3d 1112, 1125 [259 Cal.Rptr. 473, 774 P.2d 146].) In passing on an original motion to change venue, the court considers such factors as the nature and gravity of the offense, the size of the community, the status of the defendant, the popularity and prominence of the victim, and the nature and extent of the publicity. (People v. Bonin (1988) 46 Cal.3d 659, 672 [250 Cal.Rptr. 687, 758 P.2d 1217]; People v. Harris (1981) 28 Cal.3d 935, 948 [171 Cal.Rptr. 679, 623 P.2d 240].) The same factors apply to a second change of venue (People v. Gallego (1990) 52 Cal. 3d 115, 167 [276 Cal.Rptr. 679, 802 P.2d 169]) except that, as discussed below, the fact that venue has already been changed once affects the analysis. On appeal after a judgment following the denial of a change of venue, the defendant must show both that the court erred in denying the change of venue motion, i.e., that at the time of the motion it was reasonably likely that a fair trial could not be had in the current county, and that the error was prejudicial, i.e., that a fair trial was not in fact had. (People v. Douglas (1990) 50 Cal.3d 468, 541-542 [268 Cal.Rptr. 126, 788 P.2d 640] [conc. opn. of Mosk, J.].) The trial court’s essentially factual determinations such as the gravity of the crimes, the size of the community, the status of the defendant and victims, and the nature and extent of the pretrial publicity, will be sustained if supported by substantial evidence. We independently review the trial court’s ultimate determination of the reasonable likelihood of an unfair trial. (People v. Bonin, supra, 46 Cal. 3d at pp. 676-677.) The size of the community weighed heavily against a second change of venue. As noted in the appeal of Robert Alton Harris, another highly publicized capital case, San Diego County was third in the state in population and ninth in area. The City of San Diego, where the trial took place, is the second largest city in the state. (People v. Harris, supra, 28 Cal. 3d at p. 949.) In Harris, we held that this “tipped the balance” against even a first change of venue because the “ ‘adversities of publicity are considerably offset if trial is conducted in a populous metropolitan area.’ ” (Ibid., quoting People v. Manson (1976) 61 Cal.App.3d 102, 189 [132 Cal.Rptr. 265].) The gravity of the offense in this case is most serious, but this factor alone does not compel a change of venue. The status of the defendant and victims, an important factor in the initial change of venue, also weighs against the second change of venue. Neither the victims nor defendant were residents or otherwise closely associated with San Diego County. (People v. Gallego, supra, 52 Cal.3d at p. 167.) Defendant relies primarily on the factor of publicity. The court’s factual findings, however, are supported by substantial evidence. Although there was publicity, it lessened over time, and was not particularly inflammatory. It did not make it reasonably likely that the defendant could not receive a fair trial. In addition, evidence of posttransfer publicity proves little. Publicity would follow this case wherever it went. “Even if venue had been changed, nothing could have prevented the public media from swinging its attention to that place. The magnetic pull of such notorious cases is compelling.” (People v. Manson, supra, 61 Cal.App.3d at p. 177.) The 15-month time period between crime and trial also supports the court’s decision. “ ‘That time soothes and erases is a perfectly natural phenomenon, familiar to all.’ ” (People v. Bonin, supra, 46 Cal.3d at pp. 677-678, quoting Patton v. Yount (1984) 467 U.S. 1025, 1034 [81 L.Ed.2d 847, 856, 104 S.Ct. 2885].) Defendant finally contends the court erred in denying his renewed motion to change venue during jury selection, claiming the actual jury selection showed a reasonable likelihood he did not receive a fair trial. Out of over 100 prospective jurors, 8 were excused for cause because of pretrial publicity. Defendant argues that three of the actual jurors and twenty-two prospective jurors who were not excused for cause had been exposed to “prejudicial information” ranging from rape allegations against him to awareness “of some sort of confrontation that had occurred when Mr. Cooper was on a boat.” Even accepting defendant’s computation, a second change of venue was not mandated. It is speculation to suppose the results of jury selection would have been significantly different in any county. The media report local trials of notorious crimes in all counties. People read newspapers and watch television in all counties. (See People v. Manson, supra, 61 Cal.App.3d at pp. 176-177.) In addition, all of the jurors who were not excused, and especially the actual jurors, stated they could be fair. The jurors need not be totally ignorant of the facts and issues involved. “ ‘It is sufficient if the juror can lay aside his impression or opinion and render a verdict based on the evidence presented in court.’ ” (People v. Harris, supra, 28 Cal.3d at p. 950, quoting Irvin v. Dowd (1961) 366 U.S. 717, 723 [6 L.Ed.2d 751, 756, 81 S.Ct. 1639].) Although a juror’s declaration of impartiality is not conclusive (People v. Williams, supra, 48 Cal. 3d at p. 1129), the trial judge, who was on the scene and best able to evaluate the jury, was “impressed” with the overall caliber of the jurors, and found the jury to be fair. This finding of fairness is not binding on this court, but it is entitled to great weight. (See People v. Jennings (1988) 46 Cal.3d 963, 979 [251 Cal.Rptr. 278, 760 P.2d 475] [trial court’s findings regarding voluntariness of a confession entitled to great weight].) We have no reason to doubt the actual jurors’ assertions that they could be fair. (People v. Gallego, supra, 52 Cal.3d at p. 168.) It is also significant that defendant exercised only four of his twenty-six peremptory challenges. (People v. Daniels (1991) 52 Cal.3d 815, 853-854 [277 Cal.Rptr. 122, 802 P.2d 906]; People v. Coleman (1989) 48 Cal.3d 112, 136 [255 Cal.Rptr. 813, 768 P.2d 32].) Our independent review of the record convinces us that the trial court correctly denied a second change of venue. In summary, the change of venue away from San Bernardino County sufficiently protected defendant’s right to a fair trial. Trial was properly held in San Diego County. B. Jury Selection Issues 1. Juror Fees Defendant contends that the trial court’s refusal to order payment of juror fees in excess of the statutory $5 daily fee authorized by section 1143 “upset the demographic balance of the venire and resulted in the denial of a jury selected from a representative cross-section of the community.” We have repeatedly rejected the contention, and see no reason to reconsider the matter. (People v. Harris (1989) 47 Cal.3d 1047, 1076-1078 [255 Cal.Rptr. 352, 767 P.2d 619]; People v. Milan (1973) 9 Cal.3d 185, 195-196 [107 Cal.Rptr. 68, 507 P.2d 956]; see also People v. Thompson (1990) 50 Cal.3d 134, 157-159 [266 Cal.Rptr. 309, 785 P.2d 857].) Contrary to defendant’s argument, we have also held that “persons with low incomes do not constitute a cognizable class.” (People v. Johnson (1989) 47 Cal.3d 1194, 1214 [255 Cal.Rptr. 569, 767 P.2d 1047].) 2. Denial of Challenges for Cause Defendant argues the court erred in denying his challenge for cause as to six prospective jurors. Our review of the record discloses no error, but defendant has failed to show prejudice, even assuming the court erred as to all six. None was ever seated in the jury box. Defendant exercised but four of his twenty-six peremptory challenges, leaving twenty-two which could have been used to excuse the six had it been necessary. Under the circumstances, courts have found harmless the erroneous inclusion of a prospective juror. (Ross v. Oklahoma (1988) 487 U.S. 81, 87-89 [101 L.Ed.2d 80, 89-90, 108 S.Ct. 2273]; People v. Stankewitz (1990) 51 Cal.3d 72, 103 [270 Cal.Rptr. 817, 793 P.2d 23]; People v. Gordon (1990) 50 Cal.3d 1223, 1247-1248 [270 Cal.Rptr. 451, 792 P.2d 251]; People v. Bittaker (1989) 48 Cal.3d 1046, 1087-1088 [259 Cal.Rptr. 630, 774 P.2d 659]; People v. Coleman (1988) 46 Cal.3d 749, 768-771 [251 Cal.Rptr. 83, 759 P.2d 1260].) Defendant claims that because the case was tried in San Diego, the entire jury panel was so infected with prejudicial publicity that he was afraid to use additional challenges for fear the actual jury would only get worse. The record does not support the claim. We have already rejected the argument that publicity precluded trial in San Diego. The trial court found the panel to be fair. Since the 22 unexercised peremptory challenges far exceeded the number of prospective jurors defendant claims should have been excused, he has failed to show prejudice. 3. Witherspoon/Witt Contention Defendant also contends the court erred in excusing for cause two prospective jurors because of their opposition to the death penalty. We must consider this issue on the merits for, unlike the erroneous inclusion, the erroneous exclusion of a prospective juror because of that person’s views on the death penalty is reversible per se. (Gray v. Mississippi (1987) 481 U.S. 648 [95 L.Ed.2d 622, 107 S.Ct. 2045]; see People v. Coleman, supra, 46 Cal.3d at p. 768.) The applicable standard is stated in Wainwright v. Witt (1985) 469 U.S. 412 [83 L.Ed.2d 841, 105 S.Ct. 844], which “clarified” the earlier decision of Witherspoon v. Illinois (1968) 391 U.S. 510 [20 L.Ed.2d 776, 88 S.Ct. 1770]. Under Witt, a prospective juror may be excused for cause if that juror’s views on capital punishment would “ ‘prevent or substantially impair the performance of his duties as a juror in accordance with his instructions and his oath.’ ” (469 U.S. at p.424 [83 L.Ed.2d at pp. 851-852].) We have adopted the Witt standard. (People v. Douglas, supra, 50 Cal.3d at p. 523.) Defendant claims we should not apply Witt “retroactively.” We have already rejected the contention. (People v. Wright (1990) 52 Cal.3d 367, 418, fn. 16 [276 Cal.Rptr. 731, 802 P.2d 221]; People v. Gallego, supra, 52 Cal. 3d at p. 192.) The United States Supreme Court has itself applied Witt to previously tried cases. (In addition to Witt itself, see Darden v. Wainwright (1986) 477 U.S. 168, 175 [91 L.Ed.2d 144, 153-154, 106 S.Ct. 2464].) On appeal, if the prospective juror’s responses are equivocal, i.e., capable of multiple inferences, or conflicting, the trial court’s determination of that juror’s state of mind is binding. (People v. Mason (1991) 52 Cal.3d 909, 953-954 [277 Cal.Rptr. 166, 802 P.2d 950] [conflicting responses]; People v. Coleman, supra, 46 Cal.3d at pp. 766-767 [same]; People v. Ghent (1987) 43 Cal.3d 739, 768 [239 Cal.Rptr. 82, 739 P.2d 1250] [equivocal responses].) If there is no inconsistency, the only question being whether the juror’s responses in fact demonstrated an opposition to (or bias in favor of) the death penalty, we will not set aside the court’s determination if it is supported by substantial evidence and hence is not clearly erroneous. (People v. Gordon, supra, 50 Cal.3d at p. 1262.) The record supports the court’s rulings. One of the prospective jurors stated, “If I am being asked whether a man should or should not die, I cannot do it, I will not do it.” The other stated he would never vote for the death penalty. Defendant points to other, equivocal, statements, and claims the court did not sufficiently determine whether the jurors could set aside their own views and obey the court’s instructions. The court, however, resolved the question as to the juror’s true state of mind contrary to defendant, which resolution is binding on this court. (See also People v. Guzman (1988) 45 Cal.3d 915, 956 [248 Cal.Rptr. 467, 755 P.2d 917] [use of words like “I believe” or “I think” to qualify answers does not undermine a finding of substantial impairment].) We find no error. C. Pretrial Issues 1. “Hitch” Contention Relying on People v. Hitch (1974) 12 Cal.3d 641 [117 Cal.Rptr. 9, 527 P.2d 361], defendant challenged the investigation of this crime on a host of grounds, essentially contending that law enforcement authorities failed to preserve evidence in violation of his right to due process. He requested that the charges be dismissed or, in the alternative, the imposition of lesser sanctions such as prohibiting the death penalty, suppressing evidence, or giving jury instructions adverse to the prosecution regarding the allegedly lost evidence. A lengthy pretrial evidentiary hearing was held. At the end, the court, although critical of aspects of the investigation, found that all law enforcement authorities acted in good faith, and that there was no destruction of material evidence within the meaning of Hitch. The court refused to impose any sanctions, but invited the parties to “present your best shots at the time of trial to the jury on credibility . . . .” Defendant contends the court erred. He claims the authorities mishandled the investigation of the original crime scene, mishandled many specific items of evidence, and failed to collect certain items found at other locations assertedly relevant to the case. He further claims the mistakes deprived him of potentially exculpatory evidence. The applicable law is no longer found in Hitch, supra, 12 Cal.3d 641, but in two subsequent United States Supreme Court decisions. In California v. Trombetta (1984) 467 U.S. 479, 488-489 [81 L.Ed.2d 413, 422, 104 S.Ct. 2528], the high court held: “Whatever duty the Constitution imposes on the States to preserve evidence, that duty must be limited to evidence that might be expected to play a significant role in the suspect’s defense. To meet this standard of constitutional materiality [citation], evidence must both possess an exculpatory value that was apparent before the evidence was destroyed, and be of such a nature that the defendant would be unable to obtain comparable evidence by other reasonably available means.” (Fn. omitted.) More recently, in Arizona v. Youngblood (1988) 488 U.S. 51, 58 [102 L.Ed.2d 281, 289, 109 S.Ct. 333], the court held that “unless a criminal defendant can show bad faith on the part of the police, failure to preserve potentially useful evidence does not constitute a denial of due process of law.” Defendant argues that as a matter of state law we should not follow California v. Trombetta, supra, 467 U.S. 479. We have rejected the contention. (People v. Johnson, supra, 47 Cal.3d at pp. 1233-1234.) Defendant does not specifically argue that we should not follow Arizona v. Youngblood, supra, 488 U.S. 51. The reasons that caused us to adopt Trombetta in Johnson apply also to Youngblood. (See People v. Medina (1990) 51 Cal.3d 870, 894 [274 Cal.Rptr. 849, 799 P.2d 1282] [in which we implicitly followed Youngblood].) Defendant’s due process contentions fail under both Trombetta and Youngblood. Although a perfect investigation might have uncovered additional evidence, the large amount that was discovered all pointed directly at defendant. Additional evidence would have been “much more likely” to inculpate defendant than to exculpate him. (California v. Trombetta, supra, 467 U.S. at p.489 [81 L.Ed.2d at p. 422].) Nothing in the record suggests that any additional evidence would have been exculpatory, or that any exculpatory value was apparent at the time any evidence was lost. (People v. Daniels, supra, 52 Cal.3d at p. 855.) Defendant has also failed to show bad faith. The court below expressly found the investigators acted in good faith, a finding not challenged on appeal and fully supported by the record. This was a major and complex crime investigation. Although in hindsight one might criticize the investigation in a number of respects, the large number of persons involved all acted in good faith. Defendant contends that, at a minimum, the court should have given a favorable jury instruction under People v. Zamora (1980) 28 Cal.3d 88 [167 Cal.Rptr. 573, 615 P.2d 1361], In Arizona v. Youngblood, supra, 488 U.S. at page 54 [102 L.Ed.2d at page 287], for example, the trial court instructed the jury “that if they found the State had destroyed or lost evidence, they might ‘infer that the true fact is against the State’s interest.’ ” Nothing in Youngblood suggested the instruction was required. Although an adverse instruction may be a proper response to a due process violation (see Zamora, supra, 28 Cal. 3d at p. 96), there was no such violation in this case. The trial court was not required to impose any sanction, including jury instructions. (People v. Douglas, supra, 50 Cal.3d at p. 513; People v. Martinez (1989) 207 Cal.App.3d 1204, 1218 [255 Cal.Rptr. 691]; see also People v. Medina, supra, 51 Cal.3d at pp. 893-894 [finding no sua sponte duty to give an adverse instruction].) The trial court’s refusal to sanction the prosecution did not leave defendant helpless. As the court stated, he was entitled to take his “best shot” before the jury, and present evidence regarding deficiencies in the investigation to try to discredit the case against him. “This was adequate to insure a fair hearing and was itself a sufficient sanction.” (Scott v. Meese (1985) 174 Cal.App.3d 249, 258 [219 Cal.Rptr. 857].) The “Hitch" motions were properly denied. 2. Serological Evidence Defendant contends the court erred in admitting (1) the results of electrophoretic analysis of the bloodstain evidence; and (2) the testing of saliva from the two cigarette butts found in the Ryen car for secretor or nonsecretor status. He contends the evidence was inadmissible under the Kelly/Frye rule. (People v. Kelly (1976) 17 Cal.3d 24, 30 [130 Cal.Rptr. 144, 549 P.2d 1240]; Frye v. United States (D.C. Cir. 1923) 293 Fed. 1013, 1014 [54 App.D.C. 46, 34 A.L.R. 145]; see generally People v. Morris, ante, 152, at p. 206 [279 Cal.Rptr. 720, 807 P.2d 949].) At a pretrial evidentiary hearing, the prosecution presented five witnesses in support of the evidence. The defense presented none. The court admitted all the contested evidence. The Attorney General first contends that defendant has waived some of his current contentions by failing to specifically object below. (Evid. Code, § 353, subd. (a); People v. Green (1980) 27 Cal.3d 1, 22 & fn. 8 [164 Cal.Rptr. 1, 609 P.2d 468].) However, the evidentiary hearing was held in response to defendant’s Kelly/Frye objection to all of the serological evidence. The hearing and court’s ruling covered all of the matters currently in dispute. We believe defendant sufficiently objected on the grounds raised on appeal. Hence, we address the merits. Defendant challenges the general admissibility of electrophoretic testing of dried bloodstains. We recently considered and rejected this contention. (People v. Morris, supra, ante, at pp. 206-208; see also the cases cited therein.) Nothing in the instant record causes us to reconsider the matter. Defendant also challenges the admissibility of two specific tests, one involving electrophoresis, one not. He first challenges the electrophoretic testing of the drop of blood for a serum protein called transferrin. Electrophoresis is used to test for various enzymes and serum proteins, of which transferrin is only one. There was evidence that the method had only recently been used to test for transferrin. Based upon this testimony, defendant contends that testing for transferrin is of too recent vintage to have achieved general acceptance in the scientific community. All of the experts, however, who testified on the matter said that testing for transferrin was a valid application of established electrophoretic methods. In the absence of contrary evidence, there is no reason to reject a particular application of a method such as electrophoresis that has been accepted as reliable. (See People v. Smith (1989) 215 Cal.App.3d 19, 27, fn. 4 [263 Cal.Rptr. 678] [once electrophoresis is admissible, criticism of any specific methodology goes to the weight of the evidence, not its admissibility].) Defendant next challenges the testing of the two cigarette butts. Some persons secrete their ABO blood-group substance into other body fluids such as saliva. Others do not. Defendant is a nonsecretor. Gregonis performed what is called the “absorption-inhibition” test to try to determine whether saliva found on the butts was from a secretor. A positive result would have meant the saliva was from a secretor, and thus not from defendant. The result was negative. The defense never challenged the validity of the absorption-inhibition test when the result is positive. A positive result proves the donor is a secretor. Defendant argues, however, that the opposite is not true, that is, that a negative result does not prove the donor was a nonsecretor. The testimony at the hearing supports this argument. The witnesses testified that a negative result means either that the donor was a nonsecretor or was a secretor but for some reason the secretion could not be detected. An additional test, not performed in this case, would be necessary to establish that the donor was a nonsecretor. Although defendant’s argument is factually supported, it proves nothing. No one, including Gregonis, claimed more for the test than the evidence warrants. The jury learned that the test’s negative result meant that the defendant could not be excluded as a possible donor. It was not told the test affirmatively established that the donor was a nonsecretor. Gregonis testified before the jury that the negative result was an “indication” that the person was a nonsecretor, meaning that it was “more consistent” with that conclusion. He also testified, however, that the test was not conclusive, and the donor “could also have been a secretor” but the secretion was not detected. The evidence was not particularly probative, but it was certainly relevant for the jury to learn that the cigarettes were tested, and defendant was not excluded. We find no violation of the Kelly/Frye rule. Defendant also contends that Gregonis was unqualified to do the testing and to testify as an expert. The trial court, however, found him qualified. “The trial court is given considerable latitude in determining the qualifications of an expert and its ruling will not be disturbed on appeal unless a manifest abuse of discretion is shown.” (People v. Kelly, supra, 17 Cal.3d at p. 39.) Gregonis had been a criminalist in San Bernardino County for over four years with a bachelor of science degree in criminalistics. He had considerable training and practical experience in serology in general and electrophoresis in particular, and had qualified as an expert many times in the past. The court did not abuse its discretion. In a related vein, defendant also criticizes the precise manner in which Gregonis performed the tests. These arguments misperceive the nature of the Kelly/Frye rule. “[T]he Kelly/Frye rule tests the fundamental validity of a new scientific methodology, not the degree of professionalism with which it is applied. [Citation.] Careless testing alfects the weight of the evidence and not its admissibility, and must be attacked on cross-examination or by other expert testimony.” (People v. Farmer (1989) 47 Cal.3d 888, 913 [254 Cal.Rptr. 508, 765 P.2d 940].) “Once the court acts within its discretion and finds the witness qualified, as it did in this case, the weight to be given the testimony is for the jury to decide.” (People v. Smith, supra, 215 Cal.App.3d at p. 27.) Defendant was allowed to cross-examine Gregonis fully about his qualifications and the manner in which he did the testing, and to present whatever additional evidence he desired. (Id. at p. 28.) There was no error. 3. Defense Testing of Evidence During the preliminary hearing, it was discovered that a series of tiny drops of blood collected from the Ryen house had not been analyzed scientifically. The defense filed a written motion for the release of this series for independent testing. The district attorney objected because the blood drops were so small that serological testing would entirely consume them. He requested that testing be done jointly by the prosecution and defense or, alternatively, that the People test the samples in the presence of the defense expert. The defense agreed the samples were so small that they could be subjected to only one or two tests before they would be entirely consumed, but insisted on the right to analyze—and thus consume—some of the samples unilaterally without revealing the results to the prosecution until after the defense had presented its evidence at trial. Defense counsel argued that anything less would violate the right against self-incrimination because “If a trained criminalist were to know which test was done, they would be able to know what I was looking for. If they were able to know what I was looking for, they would be able to figure out certain aspects of defense strategy.” The court denied the defense motion “to release absolutely,” and asked the parties to try to agree on a method in which “both sides may participate in the testing and analysis.” At the next hearing, the district attorney was willing to allow the defense expert to “choose all the tests for all the samples,” provided only that the prosecution expert also be present at the testing. The defense wanted to be given half of the samples, and be allowed to consume them in testing, without informing the prosecution of the results. The court ordered that testing of all samples be done in the presence of both prosecution and defense experts. The evidence was eventually tested, apparently in conjunction with the defense expert. Nothing of significance was discovered. Defendant contends the court erred in not allowing independent testing of the blood samples “in a manner consistent with the privilege against self-incrimination and the right to effective assistance of counsel.” He relies primarily on cases involving the right to the effective assistance of counsel, the right to employ experts, and the privilege against being required to provide discovery to the prosecution. None is apposite. In this case, the blood samples were so small they could not effectively be divided to give the defense a portion. Under these facts, the defendant has no right to obtain the evidence collected by the prosecution, to destroy that evidence in independent testing, and then to withhold from the prosecution the results of the testing. In People v. Meredith (1981) 29 Cal.3d 682 [175 Cal.Rptr. 612, 631 P.2d 46], a murder and robbery suspect told his attorney that he had taken the victim’s wallet and disposed of it in a trash can. At counsel’s request, a defense investigator removed the wallet from the trash can. Counsel examined the wallet and turned it over to the police. The defendant contended that evidence of where the investigator found the wallet came within the attorney-client privilege, and was thus inadmissible at a trial against him. (Id. at p. 686.) We rejected the contention for reasons instructive in this case: “When defense counsel alters or removes physical evidence, he necessarily deprives the prosecution of the opportunity to observe that evidence in its original condition . . . . [T]o bar admission of testimony concerning the original condition and location of the evidence in such a case permits the defense in effect to ’destroy’ critical information; it is as if . . . the wallet in this case bore a tag bearing the words ‘located in the trash can by Scott’s residence,’ and the defense, by taking the wallet, destroyed this tag. To extend the attorney-client privilege to a case in which the defense removed evidence might encourage defense counsel to race the police to seize critical evidence.” (Id. at p. 694.) Just as there was no defense right in Meredith, supra, 29 Cal. 3d 682, to destroy evidence it found before the prosecution found it, so too there is no defense right to destroy evidence found by the prosecution. Defendant argues that if he were compelled to inform the prosecution what tests he wanted to perform, he would be forced to implicitly divulge defense strategy. The defense was not, however, compelled to do anything. The prosecution and court allowed the defense to participate in the testing on condition that the prosecution learn the results. The defense could choose to accept the condition or not participate in the testing. Forcing such a choice does not violate the Constitution or any other provision of law. (See People v. Collins (1986) 42 Cal.3d 378, 387 [228 Cal.Rptr. 899, 722 P.2d 173] [forcing a defendant to make a difficult judgment whether to testify or to assert the right against self-incrimination is constitutional].) D. Guilt Phase Issues 1. Restriction on Defense Presentation of Evidence Defendant contends the court erroneously restricted his right to cross-examine witnesses and to present evidence regarding the investigation of this crime. Although the court generally allowed the defense wide latitude to challenge the competence of the investigation, it sustained a few prosecution objections on the basis of relevancy and Evidence Code section 352. In general, the trial court is vested with wide discretion in determining relevance and in weighing the prejudicial effect of proffered evidence against its probative value. Its rulings will not be overturned on appeal in the absence of an abuse of that discretion. (People v. Green, supra, 27 Cal.3d at p. 19; People v. Pierce (1979) 24 Cal.3d 199, 211 [155 Cal.Rptr. 657, 595 P.2d 91].) This discretion is not, however, unlimited, especially when its exercise hampers the ability of the defense to present evidence. While the trial judge has broad discretion to control the ultimate scope of cross-examination, wide latitude should be given to cross-examination designed to test the credibility of a prosecution witness in a criminal case. (People v. Belmontes (1988) 45 Cal.3d 744, 780 [248 Cal.Rptr. 126, 755 P.2d 310].) The United States Supreme Court has “ ‘recognized that the exposure of a witness’ motivation in testifying is a proper and important function of the constitutionally protected right of cross-examination.’ Davis [v. Alaska (1974) 415 U.S. 308, 316-317 (39 L.Ed.2d 347, 353-354, 94 S.Ct. 1105)] (citing Gre