Video played for a B.C. Supreme Court jury on Tuesday shows the accused terrorist sitting in the passenger seat of a pickup truck expressing his concerns to an undercover officer, who is posing as an Arab businessman.
"It's crossed my mind that I could be getting set up and as soon as I hand over the plans I'm bound to go to Guantanamo Bay," says the recently converted Muslim.
Nuttall and his wife and co-accused Amanda Korody are on trial for allegedly plotting to blow up the B.C. legislature on Canada Day 2013.
"I'm going to tell you the truth because you're my brother," he tells the officer, who cannot be identified.
"I only trust you 99 per cent. There's this one per cent of me that is still paranoid."
The footage was taken by a hidden camera in early May 2013 and shows a sallow-faced Nuttall with long hair and a wiry, grey-tinged beard, wearing a dark, pinstripe suit recently bought for him by the undercover officer.
The court heard the officer invited Nuttall to accompany him from Surrey, B.C., to Whistler the following day.
The original purpose of the trip was for the accused to hand over to the officer's associates an encrypted hard drive that allegedly contained details of a plot. The purpose was later changed so the group would meet with an unidentified courier.
Nuttall furtively rolls up the truck's window as he tells the officer his ultimate plan is to take a Via Rail train hostage in Victoria, B.C., and force the government to release Omar Khadr from prison.
Khadr was arrested in 2002 at the age of 15 for throwing a grenade that killed an American soldier in Afghanistan.
Nuttall explains that he expects the 28-year-old former Guantanamo Bay prisoner will join him in jihad, or holy war, against Canada.
There is no indication that any communication has ever occurred between Nuttall and Khadr.
"I've already crossed that line of no return," says Nuttall. "I'm going to die, which is what I want, or I am going to be set up."
"Inshallah," replies the officer, using the Arabic phrase that means "If Allah wills it." Though the officer says repeatedly throughout the conversation that the door is open if Nuttall decides he wants to drop out of any plan.
"I have no more doubt," says Nuttall following the officer's reassurances.
"If you guys were really trying to set me up you would just give me a fake bomb and tell me to go bomb a target and the bomb wouldn't go off and I would be grabbed."
In her cross-examination, Nuttall's defence attorney Marilyn Sandford questioned the undercover officer about sending Nuttall mixed messages about backing out of the plot.
"When he talks about having crossed the line of no return you didn't jump in and say, 'There is no line, there's never going to be a line and you can always back out,'" pressed Sandford.
She also questioned whether Nuttall tendency to continuously change plans sent any message about his seriousness.
"No," replied the officer.
The trial also heard on Tuesday about how police worried Nuttall may have been inspired in the immediate aftermath of the Boston Marathon bombing to attempt a similar attack in B.C.
But an undercover officer told the court he was reassured after speaking on the phone with Nuttall that the man wasn't planning an imminent copycat bombing.
Fewer than three months later, Nuttall and Korody were taken into police custody after allegedly planting homemade pressure-cooker bombs at the provincial legislature in Victoria that were similar to those used in the marathon attack.
The jury has heard that police ensured the alleged bombs were inert.
Both Nuttall and Korody have pleaded not guilty to four terrorism-related charges.
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