She has been dubbed the "trailer park Mata Hari," an attractive ex-stripper recruited by the feds to befriend identical twin brothers accused of a white-supremacist bombing and to get them to admit to the crime.
She moved into the same Oklahoma campground, dressed provocatively, used racial slurs and talked like a separatist.
And she won the brothers' confidence over a five-year period in part by sending them racy photos of herself, including a shot from behind of her in a Confederate-flag bikini bottom.
As the trial of the 61-year-old brothers winds down in federal court, defense attorneys are arguing that the government's conduct was outrageous and that the informant's actions amounted to sexual entrapment.
During closing arguments Tuesday, prosecutor Michael Morrissey told the jury that the hiring of the informant, identified in court records as Rebecca "Becca" Williams, was "entirely permissible and necessary" to the investigation of Dennis and Daniel Mahon.
"There was no use of sex to obtain evidence," he said.
The jury began deliberating whether to convict the brothers, who have pleaded not guilty, after closing statements ended late Tuesday. A verdict is expected by the end of next week.
The brothers are accused of sending a package bomb in 2004 that maimed Don Logan, a black man who was the diversity director for the Phoenix suburb of Scottsdale at the time. Logan, 54, was hospitalized for three days after the bombing and needed four operations on his hand and arm. The bombing also wounded a secretary.
Morrissey said the Mahons were believers in "racial terrorism and violence as a way to accomplish their goals."
The trial, which began Jan. 10, has been filled with drama as Williams took the stand for several days, and Logan himself described the bombing in detail for the jury.
Williams, who is 20 years younger than the Mahons, said agents with the federal Bureau of Alcohol, Tobacco, Firearms and Explosives recruited her after they worked with her brother, himself an informant, to infiltrate the Hells Angels motorcycle gang.
At the time, Williams testified, she was about to be evicted from her trailer and needed the money. She received a total of $45,000, including expenses, and said she was promised $100,000 upon the Mahons' conviction.
Investigators had her pose as a separatist who was fleeing an arrest warrant and was interested in learning about Aryan resistance and how to make a bomb so she could use one on a child molester she knew.
The story was a fabrication designed to get the brothers to open up about the Scottsdale bombing.
Williams also gave the Mahons at least two racy photos _ one that showed her in a black leather vest, fishnet stockings, chaps and a Confederate flag bikini bottom, along with a note that read, "Thought you'd love the butt shot." Another photo showed her in a white bikini top, a grenade hanging between her breasts, as she posed in front of a pickup truck and a swastika.
Prosecutors said the brothers belonged to the White Aryan Resistance, an organization that encourages members to act as "lone wolves" and commit violence against non-whites and the government. They played for jurors hundreds of hours of video and audio surveillance of the brothers and Williams.
Williams testified last month, wearing a gray pantsuit with a dress shirt buttoned up to her neck and black high heels, her long, dark hair pinned up.
Under tense cross-examination, she acknowledged previously being an exotic dancer and became bashful when asked whether she knows how to use her body around men.
The "Mata Hari" nickname that the defense gave her at the beginning of the trial is a reference to the exotic dancer convicted of working as a spy for Germany during World War I.
During closing arguments, defense attorney Deborah Williams accused the government of acting like a "pimp" to get the Mahons talking.
"What you have in Dennis Mahon is a loud-mouth _ sometimes drunk ... and looking for the attentions of a younger woman who throws herself at him, and she works him like she once worked a pole," Deborah Williams said. "And of course he fell for it."
The defense attorney also referred to footage of the informant covering up a video camera with a towel after a naked Dennis Mahon got into her hotel bed. Prosecutors said Rebecca Williams gave him a foot rub; the defense attorney said that was ridiculous.
"The whole investigation was scripted around sex, sex and more sex, from the grenade between the breasts to the sleeping with him," Deborah Williams said.
Judge David Campbell urged jurors to exercise particular caution when considering Williams' testimony, since she was paid for her involvement.
The Mahons, who were living in the Phoenix area at the time of the bombing but left days afterward and were arrested in 2009 in Davis Junction, Ill., are charged with various explosives-related offenses, including conspiracy to damage buildings and property.
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