ORDER

The opinion filed September 15, 2010, slip op. 14097, and reported at 622 F.3d 1075 , is amended by deleting the penultimate sentence in the third paragraph of the opinion, slip op. at 14103, 622 F.3d at 1078, which states: <> and replacing it with: < >

With this amendment, the panel votes to deny the government’s petition for panel rehearing. No further petitions for rehearing will be entertained.

OPINION

In May 2001, several radical environmentalists decided to take a stand against genetic engineering. They did not protest; they distributed no literature. Instead, they opted for a more direct approach: they selected two targets that they (erroneously) believed were engaged in genetic engineering, and burnt them to the ground.

One of the targets was the office of Dr. Toby Bradshaw, a professor at the Center for Urban Horticulture at the University of Washington (“UW”). The fire, started with a homemade, timed incendiary device, spread from Professor Bradshaw’s office to the rest of the building, damaging several rare books in the library and ultimately causing more than $6 million in damage.

An investigation into the fires led the government to believe that Briana Waters, the defendant before us, was involved. She was eventually indicted on two counts of arson, one count of conspiracy to commit arson, possession of an unregistered firearm, and use of a destructive device during a crime of violence. A jury convicted Waters of both counts of arson, but was deadlocked on the remaining charges. She was sentenced to six years’ imprisonment.

Waters now appeals her conviction. Having reviewed the record of the proceedings below, we conclude that Waters’ trial suffered from a number of errors. Because the government has not convinced us that Waters’ verdict was unaffected by those errors, we reverse her conviction and remand for a new trial.

I.

A.

At the center of this case is a radical environmental organization known as the Earth Liberation Front (“ELF”). Both ELF and its companion organization, the Animal Liberation Front, are considered “domestic terrorist” groups by the FBI. The groups advocate using “economic sabotage” to undermine the “capitalist state,” which they blame for the destruction and subordination of the environment. Although a central tenet of both groups is to “take all necessary precautions against harming any animal — human and nonhuman,” the groups strive to inflict as much damage on economic targets as possible. In particular, the groups target those enterprises that they perceive to be “profiting off the destruction of the natural environment.”

Fire has been ELF’s weapon of choice, and the group has committed a number of high-profile arsons over the past 15 years. In 1998, for example, ELF claimed responsibility for an arson at Vail Ski Resort in Colorado. The fire damaged several chairlifts and destroyed a new mountaintop lodge, ultimately causing more than $12 million in damage. See Deborah Frazier, et al., Arson Confirmed at Vail: Investigators Discover Plastic Jugs that Had Contained Gasoline, Take Casts of Shoe Prints, Denver Rocky Mountain News, Oct. 23, 1998, at 7A, available at 1998 WLNR 828998. ELF’s costliest arson to date, which caused more than $50 million in damages, burned a new, 206-unit apartment building in San Diego to the ground. See Pauline Repard, Militants Say they Set $50 Million Condo Blaze: Earth Liberation Front Posts Claim on Web Site, San Diego Union-Tribune, Sept. 9, 2003, at Bl, available at 2003 WLNR 16778636. On a smaller scale, ELF members have repeatedly attacked “McMansions” and SUV dealerships. See, e.g., Steve Miletich, Hunt is on: Who Torched the Street of Dreams?, Seattle Times, Mar. 4, 2008, at Al, available at 2008 WLNR 4342378; State v. Luers, 211 Or.App. 34 , 153 P.3d 688 , modified, 213 Or.App. 389 , 160 P.3d 1013 (2007); United States v. Cottrell, 333 Fed.Appx. 213 (9th Cir.2009). As the Seventh Circuit recently described when cataloging the breadth of ELF’s destruction:

United States v. Christianson, 586 F.3d 532, 538 (7th Cir.2009).

Like many similar organizations, ELF operates without a structured, central hierarchy; it has no formal leadership, membership, or official spokesperson. Instead, the organization uses an “anonymous cell structure.” Individuals or cells independently plan their own actions, and use the name ELF to convey their common purpose.

B.

The arson at issue in this case started in the early morning hours of May 21, 2001. The same morning, another fire destroyed the Jefferson Poplar Farm, hundreds of miles away in Clatskanie, Oregon. At the site of the Oregon fire, the words “You cannot control what is wild” and “ELF” were spray painted on one of the surviving buildings. A communique from ELF later claimed responsibility for both fires.

The investigation into these fires saw little progress until 2004, when a man suspected of participating in the Oregon arson agreed to cooperate. With the help of this witness, the case broke wide open. The government came to believe that the UW arson had been the work of five individuals, although which five was a matter of some debate. Authorities were certain of the identities of three participants. Lacey Phillabaum and Jennifer Kolar, both seasoned ELF members, admitted to participating in the arson. William Rodgers, the man the government described as the head of the ELF cell that committed many of the arsons across the West, was identified by both Phillabaum and Kolar as a third member. Rodgers committed suicide while in jail shortly after he was arrested.

The identities of the final two participants were less clear. Kolar was the first to give a statement to the FBI, but her memory was hazy. She named the participants as herself, Rodgers, and three individuals whom she described as “Capitol Hill Girl,” Capitol Hill Girl’s “punk boyfriend,” and “Crazy Dan.” The agents ultimately learned the identities of these individuals and determined that none of them had been involved in the UW arson. A few weeks after making her initial statement, Kolar returned to the FBI and told them that she had remembered Waters’ involvement in the crime. Kolar claimed that she had remembered Waters’ involvement after coming across Waters’ name in her telephone’s contact list. Kolar never identified the remaining two arsonists, and never named Phillabaum as a participant, despite the fact that the two had a long acquaintanceship, including attending various small meetings together where they discussed environmental sabotage.

Two months after Kolar’s proffer, Phillabaum met with the FBI. She confessed to her participation in the UW arson and told investigators that the remaining four participants were Rodgers, Kolar, Waters, and Waters’ boyfriend, Justin Solondz. A search of Solondz’s residence soon thereafter uncovered evidence that he had been involved in the arson. He fled the country before police could find him.

Based on this information, a grand jury indicted Waters and Solondz, along with three individuals who had been involved in the Jefferson Poplar arson. Phillabaum and Kolar pled guilty to separate charges, and were sentenced to three and five years’ imprisonment, respectively.

C.

Phillabaum and Kolar were key witnesses in Waters’ trial, both giving detailed accounts of Waters’ role in the arson. Both agreed that Waters was not significantly involved with ELF and did not attend the initial meetings in which the UW and Jefferson Poplar arsons were planned. In May 2001, however, close to two weeks before the UW arson was to take place, Waters joined the plot to destroy the UW Center for Urban Horticulture. She attended a meeting at a Denny’s restaurant in Olympia with Phillabaum, Solondz, Kolar, and Rodgers. The five held two other meetings shortly thereafter.

Kolar and Phillabaum also gave similar descriptions of the night the arson occurred. They both testified that the five arsonists met at the Greenlake Bar & Grill in Seattle on the night of May 20, 2001. After midnight, the group drove to the Center for Urban Horticulture on the UW campus. Waters acted as a lookout, hiding in nearby bushes with a police scanner and walkie-talkie. The remaining four arsonists carried the incendiary devices to the Center for Urban Horticulture. Kolar cut into a window, after which Rodgers and Solondz climbed in and set the devices. The arsonists then returned to Waters, and they all drove away. Some time after 3 a.m., the incendiary devices ignited, starting a fire that would destroy the building.

The government was able to corroborate some of this testimony through another witness, Robert Corrina. For example, both Phillabaum and Kolar testified that Waters was in charge of obtaining a car that they would use for the arson. Waters told them that she would have a “distant, untraceable” relative rent a car for her. Corrina was that relative. He and Waters were cousins and, at the time of the UW arson, Waters was living in Corrina’s basement in Olympia.

Corrina testified that on May 19, 2001, his wife rented a car at Waters’ request. The next evening, Waters complained of abdominal pains. She and Solondz left in the rental car, purportedly to go to the hospital. Waters did not return until Monday, May 21. She told Corrina that they had been unable to find an emergency room in Olympia and had driven to Seattle. Records obtained from the car rental company indicated that the car was returned sometime before 6:30 a.m. on May 21. The records also indicated that the car had been driven 237 miles, a distance sufficient to cover a roundtrip between Olympia and Seattle.

Waters’ defense was that she was being set up by Phillabaum and Kolar, both of whom she claimed held grudges against her. She offered little in the way of an alibi and was unable directly to contradict much of the testimony against her. Instead, she focused on highlighting discrepancies in the government’s case and attacking the FBI’s investigation.

Much of Waters’ defense was spent trying to convince the jury that she did not agree with ELF’s tactics. She testified that she was “absolutely not” involved in the UW arson because it was “very dangerous to human lives,” and she felt “very strongly about not hurting people in any way.” Waters also called a number of character witnesses in her defense. These witnesses generally agreed that Waters was kind, peaceful, and responsible. They included an Assistant Attorney General for the State of Washington, Waters’ former college professors, a mother whose children Waters had babysat, and some who had worked with Waters during the making of a documentary film. They testified that Waters was not violent and never advocated violence, that she was full of “integrity” and “peacefulness,” and that she was “extremely ethical.”

After hearing the above testimony, the jury returned a verdict finding Waters guilty of two counts of arson and deadlocked on five other charges. She was later sentenced to six years in prison. She filed a timely appeal, and now raises a number of challenges to the conduct of her trial.

II.

We begin by reviewing Waters’ challenges to the district court’s evidentiary rulings. We review a district court’s evidentiary rulings for an abuse of discre tion and its interpretation of the Federal Rules of Evidence de novo. United States v. Yida, 498 F.3d 945, 949 (9th Cir.2007). We also review de novo whether a district court’s evidentiary rulings violated a defendant’s constitutional rights. United States v. Bahamonde, 445 F.3d 1225 , 1228 n. 2 (9th Cir.2006).

A.

Waters first contends that the district court erred when it barred her from introducing evidence of government misconduct. She argues that government agents conspired to conceal exculpatory evidence from her, and she asserts that her due process rights were violated when the district court prohibited her from presenting this theory of the case to the jury.

Waters’ theory of government misconduct stems from Kolar’s misidentifícation of Waters at her initial interview with the government. At that interview, as memorialized by the FBI agents’ notes, Kolar definitively identified Rodgers as a participant in the robbery, and tentatively identified the other participants as “Capitol Hill girl,” her “punk boyfriend,” and “Crazy Dan.” It is undisputed that none of these nicknames referred to Waters.

The FBI agents’ official report of Kolar’s interview took more than a month to prepare. In the interim, Kolar came forward with Waters’ name. When the FBI agents finalized their report, they did not disclose the nicknames that Kolar had originally provided to them, nicknames that conflicted with Kolar’s subsequent statement that Waters was involved. Instead, their report stated only that Kolar had originally identified the arsonists as herself, Rodgers, and “a few other individuals.”