In March, Monteilh claimed his FBI handlers had given him explicit permission to have sex with Muslim women in the community as part of his infiltration. An undercover law enforcement officer would be subject to severe disciplinary action for having sex with a target.
"Big problem. You'd get fired, and there'd be criminal prosecution as well," says David Gomez, a former FBI agent who spent years investigating domestic terrorism. "The sex itself is not criminal, but depending on the outcome and what the court says, it would be very bad."
Even though Monteilh was not an agent, his handlers could still be on the hook for his activities -- but likely only if they explicitly told him to do it.
"There are degrees of participation, and it depends on how much you're acting on the direction of the FBI," Gomez explains. "In other words, if the FBI directed you to have sex with somebody and you had sex with them, the FBI would be liable for that."
Monteilh's blizzard of claims are best taken with a large grain of salt, at least until they are resolved in court, but other sources have raised questions about his behavior. Monteilh was so zealously militant that some of his targets informed on the informant, voluntarily reporting his "jihad talk" to the FBI.
Such aggressive plays in the post-9/11 era have come under heavy scrutiny. Shahed Hussain is a Pakistani national who made tens of thousands of dollars working as a professional informant for the FBI in an unknown number of investigations on at least three continents since 2002. His work became the center of controversy in 2011 during the trial of four U.S. citizens for a synagogue bombing plot two years earlier in New York.
Once again, the informant had no prior connection to the subjects of his investigation. Hussain showed up at the local mosque and probed for anyone who would join him in radical talk. He eventually "revealed" himself as a flush terrorist financier and threw money around liberally to prove it. In a key exchange, Hussain offered $250,000 to one of the suspects, James Cromitie, who was wavering about taking part in the bombing.
"That case wasn't a terrorism plot. It was a murder-for-hire case," says the ACLU's German. "If I get $250,000, I guarantee you I can find a lot of people willing to do a lot of really horrible things."
During sentencing, U.S. District Judge Colleen McMahon also excoriated the FBI's handling of the investigation.
"The essence of what occurred here is that a government, understandably zealous to protect its citizens from terrorism, came upon a man both bigoted and suggestible, one who was incapable of committing an act of terrorism on his own," McMahon said, adding at a different point in the proceeding, "Only the government could have made a terrorist out of Mr. Cromitie."
But for all her harsh language, McMahon conceded that the men were indeed guilty of committing crimes and sentenced them each to 25 years in prison.
Similar concerns were raised in the case of Rezwan Ferdaus, a Massachusetts man arrested in 2011 who believed he was part of a terrorist cell plotting to bomb the Pentagon. Everyone else in his "cell" worked for the government, including two undercover agents and an informant with a heroin problem. During bail proceedings, his attorneys tried to impeach the informant's credibility based on drug use, but their arguments fell on deaf ears. Ferdaus pleaded guilty in July and faces 17 years in prison.
Therein lies the rub. In the vast majority of cases, the government's use of professional informants has stood up in court, year after year and case after case. For the most part, these tactics withstand the legal test, and the courts have substantial power to correct excesses when they occur. Perhaps the more important question is whether these tactics are desirable and whether Americans will continue to accept them.
What's fair play?
Should law enforcement officials be able to employ virtual agents who can skirt restrictions that would tie the hand of sworn officers? Is it acceptable for professional informants to use sex to establish themselves with suspects? Is it fair to prosecute someone whose path toward terrorism is shepherded, prodded, cajoled, and financed at every stage of the plot?
"You come to a situation where a person has indicated they want to do something, perhaps something illegal, but has taken no actual steps to accomplish that until the government arrives in the guise of Santa Claus," says the ACLU's German. "It has a bag full of treats that can help the plot along, when the person actually made no effort to do it themselves. And it puts them in the strange position of saying, 'Do I embarrass myself by saying I didn't really mean it, or do I go along?'"
The informant who "snooped and pooped" among white supremacists during the 1990s believed at the time that his work was justified, to keep someone from getting hurt or stop bombs from going off.
"Years ago, I thought it was fair play," he says. "But nowadays I look at things a little differently than I did back then."
He eventually became frustrated with the inconsistency of the Justice Department's prosecution of his targets. Over time, he came to see his efforts as intelligence-gathering without clear limits.
One thing was clear, however -- the contract the FBI asked him to sign, many months after he was put on the payroll. The document, variations of which are still used with informants today, made the informant responsible for whatever he did in the course of his work. It also stipulated that the full-time, paid informant was "not an employee, partner, member of a joint venture, associate, or Agent of the FBI."
He was simply a concerned citizen, who took "suggestions" and received a regular paycheck, for the better part of a decade.