Have US anti-terror tactics strayed into entrapment?
Watch Gordon Corera's Newsnight report in full
By Gordon Corera
Security correspondent, BBC News
In May 2009 David Williams was keeping watch at the corner of 246th Street and Independence Avenue in the Bronx, New York - the look out for a terror group aiming to blow up a building nearby.
The target was the Riverdale Jewish Center where the terror cell's leader, James Cromitie, was planting what he believed to be two devices containing C-4 plastic explosive.
Ring leader Cromitie was offered money in order to carry out the attacks
Having completed their task, the four man team planned to then head back to their hometown of Newburgh, a run-down town 60 miles (97km) north of New York City, where they intended to use a surface-to-air missile to take down a military plane at the Stewart Air National Guard Base.
The weapons had been provided by a Pakistani man.
A few weeks earlier he had met the four men to discuss the attacks. He had accompanied them as they selected a site from which to fire the missile and he was also with them when they bought mobile phones for the plot, and travelled to a Connecticut warehouse to obtain the missile and explosives.
Before the team could return to Newburgh and attack their second target a Swat team moved in and arrested the cell - all except the Pakistani.
He was in fact an undercover informant working for the FBI, and the weapons he provided were an inactive missile and inert explosives.
The four others were subsequently found guilty of terrorism offences and each sentenced to 25 years in prison.
Befriended at mosque
So when does the desire to disrupt a terror cell cross the line into entrapment and manufacturing convictions?
These guys ain't got a passport, ain't got a driving licence... They ain't got no money. Where you going to find C-4 in the hood? You didn't stumble upon a cell. You created a cell
Alicia McWilliams, aunt of lookout David Williams
That is a question judges and juries have been grappling with in the decade since 9/11, as US authorities mount an aggressive series of prosecutions - which supporters claim have kept the country safe, but which critics maintain ensnare individuals who were no real threat.
In the Newburgh case the undercover FBI informant had befriended James Cromitie at the Newburgh mosque, a small, tidy building not far from the centre of town, in June 2008.
Cromitie was an angry convert to Islam, full of rage against Jews, who said he was upset about the war in Afghanistan.
The informant told Cromitie he was linked to a Pakistani terror group. Cromitie said he was interested in jihad.
When I visited the Newburgh mosque those who were worshipping there told me it had not taken long for them to become suspicious about the informant:
"He began to talk to some of the members of the community and they would come back and say 'this guy is talking about jihad'," Imam Salahuddin Muhammad told me.
"We automatically believed that he was a federal agent. So we decided to let people in the community know to be careful of this guy He was just fishing and he fished away here long enough that he was able to find someone."
BMW as reward
An on-off relationship developed between Cromitie and the informant over some months, in which money played a significant part.
Apparently at one stage, a sum of a quarter of a million dollars was offered to Cromitie, and according to court documents the informant even promised Cromitie his BMW if he completed a mission.
Newburgh mosque's imam says that the plot was a case of entrapment
At times, the FBI investigation went cold, but Cromitie reinitiated contact after he lost his job at WalMart.
The other three figures who made up the cell were recruited just one month before the attempted attack took place.
I met Alicia McWilliams, the aunt of look out David Williams, who told me he was especially vulnerable. A petty drug dealer not long out of prison, with a brother who was in need of expensive medical treatment.
"These guys ain't got a passport, ain't got a driving licence... They ain't got no money. Where you going to find C-4 in the hood?" she asked. "You didn't stumble upon a cell. You created a cell."
In the Newburgh case the informer had been involved in a fake driving licence racket, and after working off the charges associated with that began to be paid for informing.
Although Cromitie had expressed an interest in jihad, questions have been asked about whether he was actually capable of carrying it out without the help of the informant.
Were the authorities providing them with not just the means and opportunity, but also the motivation?
The FBI is adamant that these techniques do not constitute entrapment.
"Everything we do is carefully crafted to ensure that we are not the ones encouraging the plot," Greg Fowler, who was until recently in charge of the Joint Terrorism Task Force (JTTF) office in New York, told me.
Newburgh is not an isolated case. It is part of a much broader strategy of prevention - or pre-emption - that US authorities have pursued in the last decade, one which is becoming more controversial as evidence of home-grown radicalisation in the country mounts.
I'm really confident that we've conducted ourselves consistent with the law. People who we come into contact with are always given opportunity to go down their own road of their own volition
US Attorney General Eric Holder
According to a recent investigation by the Associated Press (AP), the New York Police Department (NYPD) has also run an aggressive intelligence gathering operation - headed by a former CIA officer - which includes running extensive networks of informers in mosques and the Muslim community to map its dynamics and look for signs of trouble.
When I put these concerns to the US Attorney General Eric Holder he defended the strategy:
"I'm really confident that we've conducted ourselves consistent with the law. People who we come into contact with are always given opportunity to go down their own road of their own volition."
In the Newburgh case, the jury agreed with the authorities and the men were found guilty and sentenced to long jail terms.
"They were convicted, but it was all entrapment. The government set it all up," argues Imam Salahuddin Muhammad.
"If the informant had not been involved in this case I guarantee you those four guys would be... somewhere on the block smoking marijuana, drinking beer and barbecuing."
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