Full opinion text
Opinion by Judge MILAN D. SMITH, JR.; Concurrence by Judge HUG. OPINION M. SMITH, Circuit Judge: Defendant-Appellant Jason Wright appeals his conviction and sentence for the transportation and possession of child pornography in violation of 18 U.S.C. § 2252A(a)(l), (a)(5)(B). Wright raises numerous issues of alleged error. First, he challenges his conviction based on insufficiency of the evidence. With respect to his conviction under 18 U.S.C. § 2252A(a)(l), Wright argues that the charged offense requires interstate transmission of child pornography files, yet there is evidence that none of the files crossed state lines. With respect to both counts of which Wright was convicted, he argues that there is no evidence proving he knew that the twenty-seven files charged in the indictment were either on his computer or contained child pornography. Second, Wright challenges the district court’s denial of his motion to suppress statements. Third, Wright maintains that he was denied a fair trial based on: (1) the district court’s exclusion of evidence under Federal Rule of Evidence 404(b); (2) prosecutorial misconduct throughout the course of the trial; (3) Wright’s limited access to a mirrored copy of the computer’s hard drive; and (4) an erroneous jury instruction that failed to require the jury to find Wright knew the files charged in the indictment existed on his computer and contained child pornography. Wright also argues that even if the court would not reverse on the basis of any of these errors individually, their cumulative effect denied him a fair trial. Finally, Wright argues that his 121-month sentence was improper. We have jurisdiction under 28 U.S.C. § 1291. We affirm in part, reverse in part, and remand to the district court for proceedings consistent with this opinion. FACTUAL AND PROCEDURAL BACKGROUND On January 16, 2003, from the FBI office in Tucson, Arizona, FBI Special Agent Robin Andrews conducted an undercover search on a file-sharing program known as an mIRC (Internet Relay Chat). Andrews came across the user name “azgymguy2” in the chat rooms “100% teensexpics” and “gayteenpics.” After typing in a “trigger” that allowed her to establish a direct connection with azgymguy2’s file-trader, the following announcement appeared: Welcome to my server. I’m fairly open to uploads, so please just upload stuff you feel is good. However, I am always looking for huge cocks, young boys and movies. I hope you enjoy your stay. Andrews downloaded thirteen files— three of which were child pornography. Andrews conducted a second session that afternoon, repeating the steps she took in the morning. This time she downloaded fifty-nine files, twenty-one of which were child pornography. Andrews conducted three more undercover sessions on January 27, January 29, and February 4, 2003. According to the government’s expert witness at trial, Sven Nielsen, Wright’s direct client-to-client connection to Andrews — that is, the connection Wright used to transport the images to Andrews — did not go through IRC servers such “that the actual traffic of sending the file or sending the chat from that point on d[id] not actually cross state lines.” Nielsen also explained that, in order to establish a direct client-to-client connection, the initial request takes “the normal IRC route,” but once the request is accepted the computers are connected directly, not through the server. Of course, while the direct client-to-client communication does not actually cross state lines, the files are still transmitted over the Internet. See Appellee’s Supp. Excerpts of Record (SER) at 165 (“if Joe clicks ‘yes’ and starts accepting the file, then my computer will send that file directly over the Internet, not going through the IRC servers”); see also United States v. Lewis, 554 F.3d 208, 211 (1st Cir.2009) (explaining that while “peer-to-peer” networks, or “direct eonnection[s]” do not travel through “central servers,” the transfers are still subject to Internet communication “associated with the underlying TCP/IP protocol” (internal quotation marks omitted)). Furthermore, Andrews testified that when she logged on to the IRC network on January 16 and eventually connected to Wright’s file-server, from which Wright transported the child pornography files, she connected through a server in San Jose, California. Nee SER at 63; see also id. at 77 (same with respect to afternoon session on January 16); id. at 142 (January 27 session took place via a server in Fairfax, Virginia); id. at 167 (“[Tjypically the way people connect to an IRC server is they just say connect me to the undernet and just pick a server for me.”). After matching Wright’s home address with “azgymguy2’s” Internet connection, the FBI executed a search warrant at Wright’s residence on February 13, 2003. Agents seized Wright’s desktop computer and a laptop from the bedroom of Wright’s roommate, Shawn Dittfurth. While other agents searched Wright’s apartment, Andrews and Detective Jeff Englander of the Pima County Sheriffs Office questioned Wright outside the apartment in an unmarked police vehicle. Approximately one week after the search, Dittfurth disappeared. According to Wright, Dittfurth unexpectedly moved out of Wright’s apartment. Wright’s defense throughout the trial was that it was Dittfurth, and not Wright, who was responsible for possession of the child pornography found on Wright’s desktop computer. Wright sought to introduce evidence at trial supporting this theory; however, as we discuss more fully below, Wright claims that the district court excluded any such evidence on the basis that Dittfurth did not testify at trial. In the Superseding Indictment, the government charged Wright with ten counts relating to the advertisement, transportation, and possession of child pornography. Count 1 alleged that Wright knowingly published a notice and advertisement seeking or offering child pornography in violation of 18 U.S.C. § 2251(c)(1)(A). The jury acquitted Wright of Count 1. The government also alleged, in Counts 4 through 10, that Wright knowingly possessed images of child pornography on separate CDs, in violation of 18 U.S.C. § 2252(a)(5)(B). Wright was also acquitted of the possession charges with respect to those images. Counts 2 and 3 are the focus of this appeal. Based on Andrews’s undercover sessions connecting to Wright’s computer, the government charged Wright with transporting nine files in Count 2. The jury convicted Wright of “knowingly transport[ing] and ship[ping] in interstate commerce, by means of a computer, child pornography.” Based on images recovered from Wright’s computer, the government charged Wright with possession of nineteen files in Count 3. Wright was convicted of “knowingly possessing] computer disks ... that contained images and films of child pornography that had been shipped and transported in interstate or foreign commerce by means of a computer.” The district court sentenced Wright to 121 months on the transportation count and 60 months on the possession count, to be served concurrently. DISCUSSION Wright raises a host of issues on appeal. First, he argues that 18 U.S.C. § 2252A(a)(l), as it existed at the time of his offense, requires interstate transmission of child pornography images. Second, Wright argues that there is no evidence proving he knew that the twenty-seven files charged in the indictment were either on his computer or contained child pornography. Third, Wright challenges the district court’s denial of his motion to suppress statements. Fourth, Wright claims he was denied a fair trial. Finally, he claims that his sentence was improper. I. 18 U.S.C. § 2252A(a)(l)’s “In Interstate Commerce” Requirement As it existed at the time of Wright’s offense in 2003, 18 U.S.C. § 2252A(a)(l) punished any person who “knowingly mail[ed], or transported] or ship[ped] in interstate or foreign commerce by any means, including by computer, any child pornography.” Whether section 2252A(a)(l)’s “in interstate ... commerce” language requires the government to prove that the images themselves traveled across state lines appears to be a question of first impression in this circuit. Wright’s principal argument is that the statute does so require. However, both parties agree that the images in question never traveled outside Arizona when Andrews downloaded them from Wright’s computer. The government counters that the statute does not require the images to cross state lines. Alternatively, it argues that while the images themselves may not have traveled across state lines, their transmission would not have occurred except for the prior communications from the defendant’s file server through the IRC network to the FBI. As a result, because those communications traveled across state lines, section 2252A(a)(l)’s jurisdictional element was satisfied. We review de novo Wright’s challenge to the sufficiency of the evidence, United States v. Green, 592 F.3d 1057, 1065 (9th Cir.2010), including questions of statutory interpretation, United States v. Youssef, 547 F.3d 1090, 1093 (9th Cir.2008). First, the government argues that section 2252A(a)(l) does not require actual transportation of child pornography across state lines. As with any statutory interpretation, we start with “the plain meaning of the statute’s text.” United States v. Nader, 542 F.3d 713, 717 (9th Cir.2008). As noted, 18 U.S.C. § 2252A(a)(l) punishes any person who “knowingly mails, or transports or ships in interstate or foreign commerce by any means, including by computer, any child pornography[.]” Our analysis turns on what Congress meant by the phrase “transports ... in interstate ... commerce.” Under the plain language of section 2252A(a)(l), the statute requires that a person mail, transport, or ship child pornography interstate. That is to say, a plain reading of the statute seems to require at least some method of interstate travel. The government’s argument that section 2252A(a)(l) does not require actual transportation across state lines relies on the Third Circuit’s decision in United States v. MacEwan, 445 F.3d 237 (2006). MacEwan addressed section 2252A(a)(2)(B) (2003), which punishes “[a]ny person who ... knowingly receives or distributes ... any material that contains child pornography that has been mailed, or shipped or transported in interstate or foreign commerce by any means, including by computer.” There, the defendant stipulated to knowingly downloading child pornography from the Internet but argued that there was no evidence indicating that the images traveled interstate. MacEwan, 445 F.3d at 241. The Third Circuit rejected reading the phrase “interstate commerce” synonymously with “interstate transmission.” Id. at 243. Accordingly, it held that the statute did not explicitly require that the child pornography images had to cross state lines, only that “they must have been transported in interstate commerce by any means, including by computer.” Id. at 244 (internal quotation marks and ellipsis omitted). The court then re-framed the issue in terms of whether Internet use, standing alone, satisfies the statute’s jurisdictional hook. See id. (asking “whether downloading an image of child pornography from the Internet [] involves the receipt of something transported in interstate commerce”). According to the MacEwan court, it does — a contention we address more fully below. Two other circuits have disagreed with the Third Circuit’s statutory reading — at least with respect to whether a materially identical statutory provision requires actual transportation across state lines. In United States v. Schaefer, 501 F.3d 1197, 1204 (2007), the Tenth Circuit rejected MacEwan’s approach as contrary to the plain terms of the statute. It faulted MacEwan for “reeast[ing] the jurisdictional requirement of the child-pornography statute into one that could be satisfied by use of an ‘interstate facility,’ ” a term absent from the statute’s text, which instead uses the “in commerce language.” Id. at 1205 (some internal quotation marks omitted). According to the Schaefer court, Congress’ use of the “in commerce language” reflected “its decision to limit federal jurisdiction and require actual movement between states to satisfy the interstate nexus.” Id. at 1201-02 (citing Circuit City Stores, Inc. v. Adams, 532 U.S. 105, 115-16, 121 S.Ct. 1302, 149 L.Ed.2d 234 (2001), and explaining that when it uses the phrase “in commerce,” Congress does not intend to regulate to the full extent of its authority under the Commerce Clause). The First Circuit adopted a similar view in United States v. Lewis, 554 F.3d 208 (2009). There, the court rejected the government’s position “that Congress intended to reach purely intrastate transmission of child pornography that used a channel or instrumentality of interstate commerce.” Id. at 212. In doing so, it looked to the jurisdictional hooks of similarly worded criminal statutes and explained that courts have interpreted Congress’ decision to criminalize transportation “in interstate or foreign commerce” of the relevant material “to require actual crossing of a state or national border.” See id. at 213-14 (citing cases); see also Smith v. Ayres, 845 F.2d 1360, 1366 (5th Cir.1988) (holding that the “in interstate or foreign commerce” language in the federal wire-fraud statute, 18 U.S.C. § 1343, “requires that the wire communication cross state lines”); United States v. Colavito, 19 F.3d 69, 71-72 (2d Cir.1994) (explaining in the context of defendant’s due process challenge to 18 U.S.C. § 2252(a)(4)(B) that the statute “lists several means by which pornography may travel between states, including the transmission of visual images across telephone lines by way of computer modems”). To be sure, “Congress uses different modifiers to the word ‘commerce’ in the design and enactment of its statutes.” Circuit City Stores, 532 U.S. at 115, 121 S.Ct. 1302. Where Congress uses the phrases “affecting commerce” or “involving commerce,” it “ ‘signals an intent to exercise [its] commerce power to the full.’ ” Id. (quoting Allied-Bruce Terminix Cos. v. Dobson, 513 U.S. 265, 277, 115 S.Ct. 834, 130 L.Ed.2d 753 (1995)). However, the phrases “in commerce” or “engaged in commerce,” “are understood to have a more limited reach.” Id.; United States v. Am. Bldg. Maintenance Indus., 422 U.S. 271, 279-81, 95 S.Ct. 2150, 45 L.Ed.2d 177 (1975) (discussing the limited scope of federal jurisdiction associated with the phrase “engaged in commerce” or “in commerce” as opposed to “the broad ‘affecting commerce’ jurisdictional language”); cf. United States v. Alderman, 565 F.3d 641, 645, 647-48 (9th Cir.2009) (holding that an identical jurisdictional hook in the felon in possession of body armor statute ensures that the statute would not criminalize body armor produced intrastate, and citing United States v. Polanco, 93 F.3d 555, 563 (9th Cir.1996), for the proposition that the same jurisdictional element in the felon in possession of a firearm statute “insures, on a case-by-case basis, that a defendant’s actions implicate interstate commerce to a constitutionally adequate degree” (internal quotation marks omitted)). As the First Circuit recognized of its own precedents, see Lewis, 554 F.3d at 213, we too have previously interpreted similarly-worded criminal statutes to require the actual crossing of state lines. In United States v. Korab, we addressed 18 U.S.C. § 875(b), in which someone is guilty of federal extortion if he “transmits in interstate commerce any communication containing any threat ... to injure the person of another.” 893 F.2d 212, 213 (9th Cir.1989) (emphasis omitted) (ellipsis in original). We held that the statute required the government to prove that the threats themselves, in that case telephone calls, traveled across state lines. Id. at 214. There, all of the threatening phone calls between the defendants and the victim took place intrastate and the one telephone call that crossed state lines did not contain threats. Id. at 213-214. Thus, while there was evidence that defendants had made an interstate telephone call to the victim, there was no evidence indicating that the call contained threats. Id. at 214. “[F]ind[ing] no evidence of threatening interstate communication,” we reversed the conviction. Id. at 215. Similarly, in United States v. Sutcliffe, we held that an identical jurisdictional hook in 18 U.S.C. § 875(c) was satisfied where the “[defendant electronically sent threats and social security numbers to internet servers located across state lines.” 505 F.3d 944, 953 (9th Cir.2007). In that case, the government presented evidence that the defendant’s website, which contained the threats, was uploaded to various servers located in multiple states. Id. Notably, we relied on MacEwan in holding that “as both the means to engage in commerce and the method by which transactions occur, the Internet is an instrumentality and channel of interstate commerce.” Id. at 953 (quoting MacEwan, 445 F.3d at 245) (alteration and internal quotation marks omitted). However, the defendant’s use of the Internet did not provide a sufficient basis to satisfy the jurisdictional hook. Rather, we went on to note that the defendant’s website, containing the threats, crossed state lines by way of Internet servers in three different states. Id. The government’s reliance on Nader, 542 F.3d 713, is misplaced. Nader addressed “whether telephone calls within a single state — intrastate rather than interstate calls — can violate the Travel Act,” 18 U.S.C. § 1952(a), which prohibits the use of “any facility in interstate or foreign commerce” with intent to further certain unlawful activity. Id. at 716 (emphasis added). In holding that intrastate telephone calls sufficed to meet the jurisdictional hook, we explained that the phrase “in interstate or foreign commerce” modified the noun “facility” rather than the verb “uses.” Id. at 717-18. Therefore, it was sufficient that the defendant’s illegal conduct involved a “facility in interstate commerce”; it was not necessary for that facility itself to be “used” in interstate commerce. Id. at 718. Because the telephone was a facility of interstate commerce, defendant’s use of the telephone in committing the offense satisfied the jurisdictional nexus. Id. at 719. By contrast, section 2252A(a)(l) does not include the word “facility.” Thus, the phrase “in interstate or foreign commerce” modifies the actus reus proscribed in the statute — mailing, transporting or shipping child pornography. Unlike the Travel Act, section 2252A(a)(l)’s jurisdictional element is focused not on the means the defendant uses to mail, transport, or ship child pornography, and its connection to interstate commerce. Rather, it requires that the defendant mail, transport, or ship child pornography interstate. Thus, our precedent indicates that criminal statutes punishing the transmission of the relevant material “in interstate or foreign commerce” require the material itself to cross state lines. Yet here, as the government concedes, none of the images Wright transported to Andrews’s computer left the state of Arizona. Indeed, none traveled outside the city of Tucson. To the extent the government also argues that use of the Internet, standing alone, satisfies section 2252A(a)(l)’s jurisdictional requirement, we reject that contention on these facts. What distinguishes this case from those cases holding that Internet use, standing alone, provides the sufficient jurisdictional nexus, is that in each of those eases it was impossible to determine whether the images in question actually crossed state lines. See MacEwan, 445 F.3d at 241-42; Lems, 554 F.3d at 210-11 (“[I]t is impossible to say with any certainty that a given packet [a message or file to be transmitted that is broken into smaller pieces] will take the shortest route in distance; the routers search for the shortest route in time.”). In the face of that uncertainty, those courts held that proof of Internet use was sufficient, reasoning that because it was just as likely that use of the Internet either remained entirely intrastate or involved multiple states, “the very interstate nature of the Internet” favored finding that the images traveled in interstate commerce. MacEwan, 445 F.3d at 244; Lewis, 554 F.3d at 215. Thus, both MacEwan and Lewis stand for the proposition that, where it is impossible to determine whether the receipt of child pornography images crossed state lines, a defendant’s use of the Internet may serve as a proxy for satisfying the interstate commerce requirement. However, the question that both MacE-wan and Lewis left unanswered is that presented by Wright’s case: whether use of the Internet, standing alone, is sufficient to satisfy the “interstate commerce” requirement where it is undisputed that the images themselves did not cross state lines. In light of our conclusion that the statute does so require, we hold that a defendant’s mere connection to the Internet does not satisfy the jurisdictional requirement where there is undisputed evidence that the files in question never crossed state lines. Perhaps recognizing this dilemma, the government offers two additional arguments. First, following the Third Circuit’s approach in MacEwan, the government re-frames the issue. The proper question, according to the government, is “whether setting up a file server to transmit child pornography through the internet by use of IRC involved transporting something in interstate commerce.” Second, the government argues that in 2008 Congress amended the statute, clarifying that it always considered the “in interstate commerce” requirement to reach images transmitted via the Internet. We address each of these arguments in turn. A. Interstate Predicate Act The government argues that while the images themselves may not have traveled across state lines, their transmission would not have occurred except for the prior communications from the defendant’s file server through the IRC network to the FBI. It is undisputed that this initial connection occurred across state lines. The government contends that it would be nonsensical to protect “ ‘necessary intermediate steps’ in pornography trafficking— such as the defendant’s intrastate DCC image transmissions that only occurred because of prior interstate communications.” Thus, according to the government, an interstate predicate act satisfies section 2252A(a)(l)’s jurisdictional element. The government initially relies on our decision in United States v. Mohrbacher, 182 F.3d 1041, 1047 (9th Cir.1999), which addressed “whether downloading images from a computer bulletin board constitutes shipping or transporting within the meaning of the terms as used in 18 U.S.C. § 2252(a)(1).” There, the defendant downloaded child pornography from a computer bulletin board in Denmark. Id. at 1043-44. After being convicted of transporting sexually explicit material in violation of 18 U.S.C. § 2252(a)(1), the defendant argued that he was convicted under the wrong section of the statute. Id. at 1043. We agreed, explaining that downloading is more akin to receiving materials than to transporting or shipping them. Id. at 1050. The government points to one isolated statement in Mohrbacher, where we said: “Those who are responsible for providing the images to a customer, by making them available on a computer bulletin board or by sending them via electronic mail, are properly charged with and convicted of shipping or transporting images under § 2252(a)(1).” Id. (emphasis omitted). Nothing in Mohrbacher is apposite to the jurisdictional question presented here. Indeed, nowhere in Mohrbacher did we even mention the jurisdictional “in interstate commerce” requirement. Rather, the language on which the government relies meant to distinguish conduct constituting shipping or transporting images, within the meaning of the statute, from receiving or possessing them under a different subsection. Mohrbacher is irrelevant for purposes of this case. Somewhat more on point is United States v. Smith, 795 F.2d 841, 846-47 (9th Cir.1986). There, the defendant mailed undeveloped, unprocessed film containing images of nude teenage girls to an out-of-state developer. Id. at 844. He argued that the unprocessed, undeveloped film did not constitute “knowingly ... mailing] any visual depiction ... of a minor engaging in sexually explicit conduct.” Id. at 845 (quoting 18 U.S.C. 2252(a)(1)(A) (emphasis added)). We rejected Smith’s argument, holding “that the exclusion of unprocessed film from the statute’s coverage would impede the child pornography laws by protecting a necessary intermediate step in the sexual exploitation of children,” because the fact that the film was undeveloped eliminated neither harm to the victims nor the incentive to produce the images. Id. at 846-47 (emphasis added); see also United States v. Kelner, 534 F.2d 1020, 1024 (2d Cir.1976) (“[W]e do not feel that Congress is powerless to regulate matters in commerce when the interstate features of the activity represent a relatively small, or in a sense unimportant, portion of the overall criminal scheme. Our problem is not whether the nexus of the activity is ‘local’ or ‘interstate’; rather, ... so long as the crime involves a necessary interstate element, the statute must be treated as valid.” (internal citations omitted)). We reject the government’s view that Wright’s entirely intrastate acts satisfy the statute’s interstate commerce requirement solely because of prior interstate activity. First, to the extent that Smith can be read to suggest that Wright’s connection to the IRC network provides an adequate basis for federal jurisdiction, this would ignore the text of section 2252A(a)(l). The statute requires that the defendant “transport ... in interstate commerce ... any child pornography.” The transportation of images is the focus, rather than the connection to a network in interstate commerce that contains child pornography. It was through Wright’s connection to the interstate network that he allegedly advertised his willingness to exchange child pornography, though he did not transport any images through those channels. To accept the government’s argument would be to sustain Wright’s Count 2 conviction based on conduct of which Wright was acquitted in Count 1. Count 1 alleged that in violation of 18 U.S.C. §§ 2251(c)(1)(A), (c)(2)(A), (d), Wright did knowingly make, print and publish a notice and advertisement seeking and offering to receive, exchange, display, distribute and reproduce visual depictions involving the use of minors engaging in sexually explicit conduct, knowing or having reason to know that such notice and advertisement will be transported in interstate or foreign commerce by means of computer. Thus, section 2251(c) punishes a person who advertises the exchange of child pornography if “such person knows or has reason to know that such ... advertisement will be transported in interstate ... commerce.” 18 U.S.C. § 2251(c)(2)(A) (2003) (emphasis added). Section 2252A(a)(l), on the other hand, requires that the defendant know he is transporting the actual images across state lines. See also Korab, 893 F.2d at 214-15 (rejecting the government’s argument that conduct in connection with the crime of which the defendant was acquitted could be used to satisfy jurisdiction). Therefore, holding that section 2252A(a)(l) can be satisfied by predicate Internet use, e.g. advertising, would conflate it with section 2251(c), of which Wright was acquitted. Second, sustaining Wright’s conviction based on interstate conduct outside the actual scope of section 2252A(a)(l) would be contrary to Korab and Sutcliffe, where we held that the act being criminalized in the statute at issue must itself travel across state lines. Indeed, Korab rejected a nearly identical argument to that now advanced by the government. In Korab, the government argued that a January 11 interstate telephone call placed by the defendants to the victim satisfied the interstate communication requirement. 893 F.2d at 214. The call concerned logistical details pertaining to the defendants’ extortionate scheme, including defendants’ specific instructions to the victim on making the payment. Id. We held such conduct insufficient to maintain a conviction; the interstate call was not an essential element of the crime since it did not contain any threats. Id. Thus, Korab rejected holding that a defendant’s interstate predicate act, though perhaps necessary to completing the offense, provides a sufficient basis for jurisdiction where that act was not an essential element of the crime of conviction. See also id. (holding that interstate communications involving threatening phone calls made after the charge set forth in the indictment were not part of the crime of conviction, and therefore could not form the basis for jurisdiction). The government provides a third reason why we should consider Wright’s prior interstate activity as a basis for jurisdiction. It argues to hold otherwise would ignore that the statute includes the transportation of child pornography “by computer.” We disagree. Congress added the phrase “by any means including by computer” following “interstate or foreign commerce” in 1988, to section 2252A’s predecessors, 18 U.S.C. §§ 2251(c)(2) and 2252(a). Pub.L. No. 100-690, § 7511,102 Stat. 4181 (1988). To be sure, adding the phrase “including by computer” signals Congress’ intent to call particular attention to computers as a “means” of interstate commerce — that is, a means by which child pornography may be transported interstate. See Webster’s Third New International Dictionary 1143 (2002) (listing among the uses of the word “include” to “call more attention to the single item or smaller class by stressing the fact of its existence or the fact of its not having been overlooked”). But that Congress listed computers as one particular means of interstate transport does not permit treating computer transport somehow differently from all other means of interstate travel. See Lewis, 554 F.3d at 214 (“The plain language of the statute indicates that we are to treat shipment or transmission by computer the same way we would shipment or transmission by any other means.”); Schaefer, 501 F.3d at 1202 (“The phrase ‘including by computer’ specifies a method of interstate movement; the government must still establish that any computer-related movement crossed state lines.”). Whether the defendant transported child pornography by mail, by sea, or by computer, the government must still prove it crossed state lines. Accordingly, we hold that an interstate predicate act — here, Wright’s connection to the IRC network — does not provide a sufficient basis for federal jurisdiction under section 2252A(a)(l). B. 2008 Amendments Next, the government argues that the Effective Child Pornography Prosecution Act of 2007 (the 2007 Act), enacted October 8, 2008, see Pub.L. No. 110-358, 122 Stat. 4001, clarified Congress’ intent that section 2252A(a)(l)’s jurisdictional hook was always meant to encompass the transmission of child pornography over the Internet, regardless of whether the files crossed state lines. The parties disagree as to whether the 2007 Act “clarified” versus “significantly expanded” section 2252A(a)(l)’s reach. See Beverly Cmty. Hosp. Ass’n v. Belshe, 132 F.3d 1259, 1265 (9th Cir.1997) (addressing whether a subsequent enactment applied to a pending case by determining whether the statute clarified or “substantially] change[d]” the law). We therefore discuss the relevant legislative history in some detail. In 1978, Congress enacted the Protection of Children Against Sexual Exploitation Act of 1977 (the 1977 Act), adding sections 2251, 2252, and 2253 to Title 18 of the United States Code. Pub.L. No. 95-225, 92 Stat. 7 (1978). In passing the 1977 Act, Congress was concerned with the connection between child pornography and child prostitution, finding that children being used both as prostitutes and as the subjects of pornographic materials had become a nationwide, multimillion dollar industry that harmed children and society as a whole. S.Rep. No. 95-438, at 5-8, reprinted, in 1978 U.S.C.C.A.N. 40, 42-45. As proposed, section 2252 stated: Any individual who knowingly transports, ships, or mails through or in such a manner as to affect interstate or foreign commerce any photograph or film depicting a child engaging in a prohibited sexual act or in the simulation of such an act, or any individual who receives for the purpose of selling or sells any such photograph or film which has been transported, shipped, or mailed through or in such a manner as to affect interstate or foreign commerce shall be fined not more than $25,000 or less than $5,000 or imprisoned not more than fifteen years or less than two years or both. Id. at 60 (emphases added). Section 2251, which prohibited the actual use of minors to engage in sexually explicit conduct, also contained the “affect commerce” language. See id. In response to the proposed bill, Assistant Attorney General Patricia M. Wald, writing on behalf of the Department of Justice, recommended that the words “affect interstate commerce or foreign commerce” be deleted. Id. at 61. While the Justice Department recognized that Congress could constitutionally proscribe such activity under its Commerce Clause power, it was concerned that the proposed language would cover purely intrastate distribution, based on the theory that commerce is ‘affected’ in that the processing of the film or photographs utilize materials that moved in interstate commerce. In our opinion, the investigation or prosecution of purely local acts of child abuse should be left to local authorities with federal involvement confined to those instances in which the mails or facilities of interstate commerce are actually used or intended to be used for distribution of the film or photographs in question. Id. (internal citations omitted). In response, Congress replaced the more broadly reaching phrase “affect interstate or foreign commerce,” with the more limited “in interstate or foreign commerce.” In doing so, Congress recognized that the jurisdictional element was an important component of preserving the balance between federal and state law enforcement responsibilities. See id. at 53-54; see also n.6 supra. In 1996, Congress enacted the Child Pornography Prevention Act (the 1996 Act), adding section 2252A to the statutory framework. Section 2252A(a)(l), the provision under which Wright was convicted that punishes the transportation of child pornography, included the same jurisdictional “in interstate or foreign commerce” element as the earlier enacted section 2252(a)(1). Compare Pub.L. No. 104-208, 110 Stat. 3009, 3009-28 (1996), with Pub.L. No. 95-225, 92 Stat. 7 (1978). While the 1996 Act left unchanged the jurisdictional hook from section 2252(a)(1), two years after passage of the 1996 Act, the 1998 Congress added a new jurisdictional basis to section 2251, which prohibits the production of child pornography. See Pub.L. No. 105-314, 112 Stat. 2974, 2977 (1998). Before 1998, section 2251 punished any person involved in the production of child pornography where such person knew or had reason to know that the pornography would be transported in interstate or foreign commerce, or if the pornography was actually so transported. See 18 U.S.C. § 2251 (1996). The 1998 Act expanded the jurisdictional reach of section 2251 to include situations in which the pornography “was produced using materials that have been mailed, shipped, or transported in interstate or foreign commerce.” 18 U.S.C. § 2251 (1998). In so amending section 2251, Congress brought the child pornography production statute in line with analogous possession statutes, which already prohibited the possession of child pornography produced using such interstate materials. See 18 U.S.C. §§ 2252(a)(4)(B), 2252A(a)(4)(B), 2252A(a)(5)(B). Congress recognized that, as previously enacted, the production statute did not account for those cases where the visual depictions had not actually crossed state lines, or where there was no proof of the producer’s knowledge that they would be so transported, and remedied its concerns by expanding the statute’s reach. See H.R. Rep. 105-557, at 26-27 (1998), reprinted in 1998 U.S.C.C.A.N. 678, 695. Thus, the 1996 Act is significant in several respects. First, in leaving unchanged the jurisdictional language of section 2252(a)(1), Congress again rejected the broader jurisdictional reach encompassed by the “affecting commerce” language. In doing so, Congress reinforced its earlier concerns with respect to maintaining the balance between federal and state law enforcement of transporting child pornography. Second, Congress chose not to bring the jurisdictional reach of the transportation offense in line with the possession offenses, as it did in 1998 with the child pornography production statute. In other words, Congress did not amend section 2252A(a)(l) to prohibit transporting any child pornography “that was produced using materials that have been mailed, or shipped or transported in interstate or foreign commerce.” In 2008, Congress passed the 2007 Act. Based in part on a finding in the 2007 Act that “[t]he transmission of child pornography using the Internet constitutes transportation in interstate commerce,” Pub.L. No. 110-358, § 102(7), Congress amended the jurisdictional provisions in sections 2251, 2252, and 2252A in a section titled “Clarifying ban on child pornography.” Pub.L. No. 110-358, § 103. Most relevant here, in section 2252A(a)(l) Congress inserted the phrase “using any means or facility of interstate or foreign commerce or” after “ships,” and replaced “in interstate” with “in or affecting interstate commerce.” 122 Stat. 4001, 4002-03. Thus, following the 2007 Act, section 2252A(a)(l) punishes “[a]ny person who knowingly mails, or transports or ships using any means or facility of interstate or foreign commerce or in or affecting interstate or foreign commerce by any means, including by computer, any child pornography.” The government argues that the 2007 Act confirms that Congress always meant for section 2252A(a)(l)’s jurisdictional element to be satisfied by any predicate use of the Internet, and that we should so construe the statute as enacted in 1996. We disagree. First, in enacting section 2252A(a)(l) in 1996, Congress made no relevant change to the jurisdictional hook inserted in the 1977 Act. The legislative history makes clear that Congress settled on the “in interstate commerce” language because of its limited scope and squarely rejected an earlier proposed bill that would have reached conduct “affecting interstate commerce.” By contrast, in 2007 Congress chose to regulate to the outer limits of its Commerce Clause authority by inserting the “affecting interstate commerce” language. See 153 Cong. Rec. H13591-92 (daily ed. Nov. 13, 2007) (statement of Rep. Conyers) (stating Congress’ intent “that the prohibitions against child pornography reach the full extent of its constitutional authority”); id. at H13592 (statement of Rep. Goodlatte) (“The proposed legislative fix ... would expand the jurisdiction to prosecute these crimes when the Internet is used. This is the broadest assertion of interstate commerce power that the Congress can make consistent with the Constitution.”); see also Circuit City Stores, 532 U.S. at 115, 121 S.Ct. 1302. In light of Congress’ earlier efforts to afford the statute a more limited jurisdictional reach, we consider the 2007 Act to have effected a substantial change in section 2252A(a)(l), rather than a clarification. See Beverly, 132 F.3d at 1265. Though Congress labeled the 2007 Act a mere clarification, to so construe it that way would ignore both as a matter of law, see Circuit City Stores, 532 U.S. at 115, 121 S.Ct. 1302, and as a matter of fact, Congress’ deliberate use of jurisdictional modifiers, see Beverly, 132 F.3d at 1266 n. 6 (Congress may formally declare that an act clarifies the law so long as doing so would not run contrary to the statute’s actual text). Second, while Congress chose to reach some wholly intrastate conduct with respect to distribution and possession of child pornography, it made no similar decision with respect to transportation. Indeed, as stated above, it explicitly rejected language that would have reached such conduct. Finally, other courts have recognized that despite the 2007 Act, they are bound by the statute as written at the time of the offense. See Lewis, 554 F.3d at 216 (interpreting the pre-amendment version of section 2252A and characterizing the 2007 Act as “expanding] the jurisdictional coverage”); United States v. Swenson, 335 Fed.Appx. 751, 753 (10th Cir.2009) (applying Schaefer and stating that “the government concedes, as it must, that this case is governed by the pre-amendment statute”). In sum, we hold that at the time of Wright’s offense, section 2252A(a)(l) required the government to prove that the child pornography images actually crossed state lines. Since it is undisputed that none of the images that form the basis of Count 2 crossed state lines, there is insufficient evidence that Wright “transported] ... in interstate ... commerce by any means, including by computer, any child pornography.” Accordingly, we reverse his Count 2 conviction. II. Wright’s Knowledge Next, Wright challenges the sufficiency of the evidence as to both Counts 2 and 3 on the basis that he did not know that the specific files charged in each count were on his computer and contained child pornography. The government counters that Wright admitted such guilty knowledge to Agent Andrews and Detective Englander and his convictions should be sustained by virtue of this confession along with sufficient corroborating evidence. Where the government relies on a defendant’s confession to meet its burden of proof, it must introduce two types of corroborating evidence: (1) “sufficient evidence to establish that the criminal conduct at the core of the offense has occurred”; and (2) “independent evidence tending to establish the trustworthiness of the admissions.” United States v. Lopez-Alvarez, 970 F.2d 583, 592 (9th Cir.1992). Wright principally challenges this second requirement, arguing that his statements should never have been introduced because they were not voluntary. Therefore, since Wright’s knowledge with respect to Counts 2 and 3 turns on whether his admissions were properly admitted, we must examine whether the district court erred in denying Wright’s motion to suppress his statements. The district court held a suppression hearing, at which Agent Andrews, Detective Englander, and Wright all testified. A number of factual disputes were revealed by their testimony. For example, Agent Andrews testified that when the FBI first entered Wright’s apartment, they placed both Wright and his roommate Dittfurth in handcuffs in order to conduct a sweep of the premises. However, at the conclusion of the initial sweep, Andrews testified that Wright’s handcuffs were removed. Andrews stated that she then asked Wright if he would like to go downstairs from the apartment and answer some questions in Englander’s car parked out front. Wright agreed to answer their questions; he testified that he felt he had no choice. According to Andrews, Wright was no longer in handcuffs when he accompanied the officers to Englander’s car. Detective Englander also testified that he did not recall Wright being handcuffed on the way to the car and stated that Wright was not handcuffed during questioning. However, Wright testified that he was initially handcuffed and thrown on the floor of his apartment for approximately fifteen minutes, and that he remained in handcuffs while being taken to Detective Eng-lander’s car and for the majority of questioning inside the car. There was also a dispute as to whether Wright was read his Miranda rights before questioning. Agent Andrews and Detective Englander both testified that Eng-lander read Wright his Miranda rights and that Wright waived those rights. However, Wright testified that he was never read his rights. Next, Wright testified that he asked on three separate occasions to speak to an attorney. Specifically, Wright stated that he asked the officers if he could get his cell phone in order to call an attorney friend. But according to Wright, he was told that he could not return to the apartment to retrieve his phone and that there was no need for him to speak with a lawyer. Both Andrews and Englander testified that Wright never requested to speak to a lawyer. Andrews, Englander, and Wright all seem to agree that the questioning lasted between forty-five minutes and an hour. Neither Andrews nor Englander tape-recorded the conversation they had with Wright. Wright argued in the district court that their failure to do so violated Wright’s due process rights. The district court denied Wright’s motion to suppress in a two-line Order: After hearing evidence and reviewing the memorandum filed by counsel, the Court will DENY the Motion to Suppress Statements (# 55). While the Court believes it would have been better if all these statements were taped, the law does not require it, the Court also cannot. The absence of any factual findings by the district court considerably frustrates our appellate review. Relying on United States v. Craighead, 539 F.3d 1073 (9th Cir.2008), Wright argues that he was in custody at the time of police questioning and was therefore entitled to Miranda warnings, which he did not receive. While determining whether a defendant is constitutionally entitled to Miranda warnings is subject to de novo review, it is nevertheless a fact-intensive inquiry. Id. at 1082, 1084; see also United States v. Kim, 292 F.3d 969, 973 (9th Cir.2002) (whether a person is “in custody” for Miranda purposes is a mixed question of law and fact; factual findings are reviewed for clear error). “[A] suspect is ... considered ‘in custody’ for purposes of Miranda if the suspect has been ‘deprived of his freedom of action in any significant way.’ ” Craighead, 539 F.3d at 1082 (quoting Miranda v. Arizona, 384 U.S. 436, 444, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966)). Yet there are several threshold factual disputes important to determining whether Wright would have felt free to leave. For example, Wright testified that he remained in handcuffs the entire time he was being questioned, a period that lasted between forty-five minutes and an hour. See United States v. Booth, 669 F.2d 1231, 1236 (9th Cir.1981) (holding that while “[h]and-cuffing a suspect does not necessarily dictate a finding of custody[,]” it is a factor the district court should consider). He also testified that he requested on three different occasions to call a friend who was an attorney, but was told that he could not return to his apartment where his phone was located. This is in stark contrast to the officers’ testimony, in which both Andrews and Englander stated that Wright never mentioned wanting to speak to a lawyer, but that had he so requested, they would have immediately stopped the interview. See Craighead, 539 F.3d at 1084 (listing among the factors to consider whether an in-home interrogation was custodial “whether the suspect was at any point restrained” and “whether the suspect was informed that he was free to leave or terminate the interview”). It is also significant that whether or not Wright was told he was free to leave, he could not simply return to his home, since it was being searched. See id. at 1088 (concluding that despite being told he was free to leave, the defendant would not have reasonably believed he was free to go because agents were searching his home); United States v. Lee, 699 F.2d 466, 467-68 (9th Cir.1982) (per curiam) (holding defendant would not have felt free to leave where he “was questioned in a closed FBI car with two officers for well over an hour while police investigators were in and around his house”). The district court must resolve these factual disputes in order for this court to address whether Wright was in custody for purposes of Miranda, and thus should have received adequate Miranda warnings. Nor can we resolve the issue by simply assuming that Wright was entitled to Miranda warnings, received them, and subsequently effected a valid waiver. The district court made no finding as to whether Wright invoked his right to counsel on the three separate occasions he requested calling his friend. At a minimum, Wright’s statements should have led the officers to clarify Wright’s intention. See United States v. de la Jara, 973 F.2d 746, 750 (9th Cir.1992). Instead, Wright testified that he was told not to worry, that he was not being arrested, and that he could not return to his apartment to get his phone. The absence of factual findings also impedes our review of Wright’s claims that his statements were not made voluntarily. “In determining the voluntariness of a confession, we ‘examine[ ] whether a defendant’s will was overborne by the circumstances surrounding the giving of a confession.’ ” Doody v. Schriro, 596 F.3d 620, 638 (9th Cir.2010) (en banc) (quoting Dickerson v. United States, 530 U.S. 428, 434, 120 S.Ct. 2326, 147 L.Ed.2d 405 (2000), vacated on other grounds sub nom., Ryan v. Doody, 78 U.S.L.W. 3715 (U.S. Oct. 12, 2010)). Voluntariness is determined by considering the totality of the circumstances, including “close scrutiny of the facts.” Id. Under Federal Rule of Criminal Procedure Rule 12(d), “[w]hen factual issues are involved in deciding a motion, the court must state its essential findings on the record.” We have held that compliance with that rule (formerly Rule 12(e)) is “particularly important in a case ... where we examine all the surrounding circumstances.” United States v. Castrillon, 716 F.2d 1279, 1282 (9th Cir.1983) (internal quotation marks omitted). As a result, “we require a statement on the record of those factual findings upon which the district court based its grant of the motion to suppress.” Id. at 1283 (remanding the question of voluntariness in the absence of adequate factual findings). The government maintains that a remand is unnecessary in this case because the district court’s factual findings are implicit in its ruling. It argues that the suppression hearing boiled down to a credibility contest, in which case the district court “unmistakably found the defendant’s testimony unbelievable, adequately finding the ‘essential’ facts required by Rule 12(d).” However, the cases on which the government relies are inapposite. For example, in United States v. Whitworth, 856 F.2d 1268, 1278 (9th Cir.1988), we held that while the district court did not specifically address the defendant’s request for counsel, implicit in the district court’s ruling was that the court believed the agent’s testimony that it was the defendant who initiated a conversation with the officers following his initial request for counsel. However, in Whitworth, the district court clearly articulated two grounds for denying the defendant’s suppression motion and provided factual findings upon which it based its ruling. Indeed, the court credited the agents’ testimony in finding both that the defendant received Miranda warnings and that his statements were made voluntarily. Id. We held that those findings were not clearly erroneous. Id. Here, the district court made no factual findings and the only theory identified in its order denying the suppression motion is that the officers were not required to record their conversation with Wright. But Wright raised a number of grounds in his motion to suppress, which required important factual disputes to be resolved. The district court gave no indication that it believed all of Agent Andrews’s and Detective Englander’s testimony and found Wright’s testimony entirely incredible. Rather, the district court seems to have avoided making any credibility determination, choosing instead to deny Wright’s suppression motion on the basis that the government was not required to record the interview. In United States v. Prieto-Villa, 910 F.2d 601, 606 (9th Cir.1990), we held that remand for factual findings is required where it is impossible to determine the basis for the district court’s denial of a motion to suppress. See also id. at 610 (holding that absent a revision to Rule 12(d), “district courts must put their essential factual findings on the record”). We recognized that earlier cases, which held that the appellate court would “affirm in the absence of factual findings if any reasonable view of the evidence would sustain the denial of the motion,” had overlooked the requirements of Rule 12(d). Id. at 607 (internal quotation marks omitted). Prieto-Villa also recognized that factual findings are particularly important in the context of suppression hearings. Id. at 609-10. Therefore, we reverse the denial of Wright’s motion to suppress and remand with instructions to the district court to make essential factual findings explaining the basis for its decision. III. Wright’s Fair Trial Claims A. Exclusion of 404(b) Evidence Next, Wright argues that the district court erred in precluding evidence that Wright’s roommate, Shawn Dittfurth, had motive, opportunity, knowledge, and the ability to obtain, view, and possess child pornography. Wright wanted to introduce evidence showing that Dittfurth had a sexual attraction to minor boys and was proficient with computers. Wright claims that the district court precluded this “prior act” evidence under Federal Rule of Evidence 404(b) because Dittfurth did not testify. The government raises two arguments in response. First, the government claims that Wright never actually offered any such evidence and therefore the district court did not preclude it. Second, the government argues that, assuming the district court did exclude the evidence, it was proper to do so, though on alternative grounds. On January 27, 2006, Wright filed a Notice of Intent To Present Other Act Evidence under Rule 404(b). Wright sought to introduce four different pieces of evidence with respect to prior acts of his roommate, Dittfurth. First, Wright intended to introduce records from Mount Saint Mary College in Newburgh, New York, showing Dittfurth received a computer competency waiver from Saint Mary’s, as well as an “A” in Computer Literacy. Wright’s theory for admission was that Dittfurth’s computer competency would show Dittfurth had the knowledge necessary to commit the charges. He intended to call a custodian of records from Saint Mary’s to testify. Second, Wright intended to introduce, through Wright’s testimony at trial, that Dittfurth lived with Wright during the relevant time period and that Dittfurth was often alone in the apartment, where he had access to Wright’s desktop computer. According to Wright, such testimony would show that Dittfurth had the opportunity to commit the alleged offenses. Third, also through Wright’s testimony, Wright intended to introduce evidence that after Wright’s apartment was searched on February 13, 2003, Dittfurth encouraged Wright to sign over to Dittfurth power of attorney to Wright’s property and businesses, and suggested that Wright flee the country before charges were filed against him. Wright theorized that this evidence would show Dittfurth had the motive, intent, plan, and preparation to commit the offenses. Finally, Wright would testify that Dittfurth visited the site gay.com, where his online identity was “Presumed Innocent.” Wright argued that this evidence would show Dittfurth’s identity and knowledge and that Dittfurth’s “on-line identity is ironic in light of this case.” Argument on Wright’s motion took place nearly a year later, on January 22, 2007. Wright’s counsel indicated that the government agreed to allow Wright to testify that Dittfurth lived with Wright during the relevant time period. However, the government contested the other three pieces of evidence, which defense counsel proceeded to address in her argument to the district court. As to each piece of evidence Wright sought to introduce, the district court asked defense counsel how the evidence was relevant should Dittfurth not testify at trial. See District Ct. Docket No. 374: Transcript of Motion Hearing dated Jan. 22, 2007 at 14 (concerning Dittfurth’s computer literacy); id. at 17 (power of attorney); id. at 19 (Presumed Innocent screen name). Likewise, the government assumed that the only way in which any of the evidence could be introduced was if Dittfurth testified. At the close of argument, the district court indicated that it agreed that evidence about Dittfurth’s computer knowledge and the statements Dittfurth allegedly made requesting Wright give Dittfurth power of attorney were both relevant; not so with respect to the Presumed Innocent screen name. The minute entry from the January 22 hearing contains the following entry: “Further 404B on Shawn Dittfurth; if he testifies, the Court finds evidence regarding testing out of computer class, and his statement to have defendant Wright turn over power of attorney to property in Mexico relevant; his use of on-line screen name of ‘presumed innocent’ is not relevant.” Appellant’s Excerpts of Record (ER) at 35 (emphasis added). In later hearings with the court, defense counsel also discussed the possibility of calling Dittfurth’s co-worker, Holly White, to testify to his credibility (since law enforcement interviewed him when they searched Wright’s apartment) and to establish Dittfurth’s interest in teenage boys. White would testify that when she worked at a skate shop with Dittfurth, he made passes at boys around the ages of 12-15. Defense counsel also discussed calling Nick Shorb, a 12-13 year old boy who worked with Dittfurth at the skate shop who would testify that Dittfurth made passes at him and showed him pornography. Both White and Shorb later appeared on Wright’s list of witnesses for trial. There was no further discussion of whether the 404(b) evidence would be coming in until the first day of trial on January 17, 2008. During her opening statement, defense counsel discussed Dittfurth at some length, including references to his knowledge of computers from his days at Saint Mary’s College, and that he encouraged Wright to go to Mexico following execution of the search warrant. After the court recessed the jury for the day, the government objected to defense counsel referring to individuals who would be testifying about Dittfurth, arguing that none of that evidence should come in unless Dittfurth testified. The government pointed out that neither it nor the defense would be calling Dittfurth to testify. The district court initially expressed its skepticism as to whether the evidence could be admitted absent Dittfurth testifying. However, the court never explicitly precluded such evidence. Rather, the district court left it to defense counsel to provide the court with a legal basis for introducing the evidence. Indeed, the district court judge stated numerous times that he was not sure if the evidence could come in without Dittfurth’s testifying, but that it was up to defense counsel to convince him otherwise. See ER at 52 (responding to the prosecutor’s statement that the evidence was not relevant without Dittfurth testifying, saying: “I haven’t crossed that road yet, either, so I’m sure Ms. Williams is going to provide some sort of legal basis to allow that to come in without Mr. Dittfurth.”); id. (“I’m having trouble seeing that, I don’t see how they’re relevant without [Dittfurth], but I’m sure Ms. Williams will show me some book if it says they are.”); id. at 53 (“I’ll still [sic] having trouble seeing how they come in without having Mr. D