Transcript for Man goes on mission to behead police officers for ISIS: Part 4
America. Reporter: Just two weeks ago a court in Massachusetts handed down a verdict on the event you are watching in this surveillance tape, a man in Boston walking through a parking lot on a murderous mission. Unfortunately, you will not be seeing me again. Reporter: His plan, to behead as many policeman as he can. We have a gentleman, black male, six feet coming out now with a knife. Reporter: He's 26 years old, has two jobs in retail at CVS, and one at Best Buy. He has also been researching his knife online, though he's having second thoughts, worried he'll back out. Firmness of intent will be taken from me, and I don't want to miss it while I have it. Because I know the afterlife is better than this one here. Reporter: But there is someone there to urge him fore for ward someone with a big smile his nephew David. That nephew is an unemployed high school graduate, born in America, Muslim family, who's spent hours and hours online. Jihadi propagana. Violent videos, and this young man is so persuasive online, prosecutors say he was the ringleader, even managing to enlist a complete stranger through his computer. The stranger is from Rhode Island. He was raised in a cat lick feel and has said his cerebral palsy made him isolated too. He was struggling for his own kind of empowerment. I've been wanting to meet up with you to discuss some important aspects I think you might uh, you might enjoy. Oh! That sounds wonderful! Reporter: The nephew decides the first target will be a woman who's on the ISIS hitlist, Pamela Geller, an activist who says she's anti sharia. The other is in another city. So the uncle decides he has a new plan to kill police. The nephew is excited. I'm going out today, those boys in blue, because it's the easiest target. Oh, oh dang those juicy necks is intense, dang. At another point he also seems to refer to the ISIS practice of putting the victims' head on top of their chest. It's as they say sometimes. You know, it's like -- Yeah. It's like thinking with your head on your chest. Holy crap! Oh god! I'm freaking insane. Reporter: Former chief prosecutor, Mary Mccord, says in so many of the 147 cases prosecuted by her office, men exert peer pressure on each other to keep each other from backing out. She says the pressure is especially powerful if there are also family ties. If a person individually might, you know, get cold feet or wanna change his mind, not only then would he be letting himself down, but he'd be letting down his co-conspirators. Reporter: Four of the 19 attackers on 9/11 were brothers, so were the Brussels suicide bombers, the Boston marathon bombers. In Chicago this mother learned that three of her teenaged children were recruited by ISIS together. Plane tickets were in their hands about to board the plane. We condemn the brainwashing and recruiting of children through the use of social media and the internet. We have a message for ISIS. Leave our children alone! Reporter: And now we are back with that man walking across the parking lot. You see him going back and forth, across another street, into the pharmacy and out. Is it possible he was still worried he'd lose his nerve? He has written out a will leaving his mother everything he has, $80 in $20 bills. Can you put your hands up please? Reporter: The police surround him, he threatens them with his knife. Why don't you drop yours? Why don't you drop yours? Why don't you drop yours? Drop it, drop it. Why don't you drop yours? Drop it drop it. Drop yours. Reporter: And strangely he has a phone which is still on a call with his bewildered father, who has no idea what's happening. Where are you? Where are you? Where are you? Come on. Why don't you shoot me? Shots fired. Reporter: The uncle is dead, and when the nephew is finally arrested we learn a kind of twist in this story. This mastermind directing events from his room with his computer, turns out to be morbidly obese, 550 pounds, and his own defense lawyer calls him quote, fat, failed, a complete idiot. She tries to argue that because he rarely left his house, and just had a computer, he was not dangerous. The jury had a different opinion. Breaking news. David Wright of refrt has been convicted, the jury had a
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