The agent's presence at the anti-Islam event in Garland, Texas, was publicly revealed months after Abdul Malik Abdul Kareem was convicted in the May 2015 attack that ended when Elton Simpson and Nadir Soofi, friends of Kareem who were Islamic State followers, were killed in a shootout with police.
The disclosure about the agent's presence led Kareem to make an unsuccessful bid for a new trial last year and raised questions about whether authorities could have done more to stop the attack.
In a court filing Monday, Kareem's attorneys asked again for a new trial, saying a prosecutor at another trial last spring in Ohio said that Erick Jamal Hendricks, who was accused of recruiting for the Islamic State, was "unequivocally tied to this attack."
Prosecutor Rebecca Magnone told the Ohio jurors that Hendricks had been in contact with Simpson, who was killed by Garland police on May 3, 2015, along with Soofi after they exited a car outside the convention center wearing body armor and carrying rifles.
The information that emerged from the Ohio trial is crucial information that could lead to a different outcome for Kareem if he is granted a new trial, his defense attorneys said.
"This is not what this court heard previously from the government in Kareem's case," wrote Daniel Drake, one of Kareem's attorneys.
After Kareem's trial ended, federal authorities said there was no substantive connection between Hendricks and the cartoon contest, Drake said.
There was no mention at Kareem's trial that an undercover agent had witnessed the shooting and exchanged social media messages with Simpson days before the attack. The agent's involvement in the case was first mentioned in court records nearly eight months after Kareem's trial ended.
Cosme Lopez, a spokesman for the U.S. Attorney's Office in Phoenix, declined to comment on Kareem's latest request. In an appellate court document filed earlier this year over Kareem's conviction, prosecutors said Kareem couldn't show the judge made in an error in rejecting the request for a new trial.
Kareem is serving a 30-year prison sentence for his convictions that included providing support to the Islamic State. Prosecutors have said Kareem trained Simpson and Soofi on how to use guns and watched jihadist videos with them.
On the day of the attack, the agent communicated with Hendricks via social media while the agent was outside the convention center where the event was held. Hendricks asked the agent about the number of officers at the scene and whether snipers were present.
The agent had been sitting in a vehicle outside the Garland convention center just as the cartoon contest ended. Moments before the shooting, he took photos of a police officer and another person standing in the distance near a tree and an image showing a parking lot.
Kareem's attorney said Hendricks put the undercover agent into contact with Simpson 10 days before the attack. In one encounter with the agent, Simpson referred to the upcoming contest in Texas.
The judge who presided over Kareem's trial had denied his first request for a new trial, saying Simpson did not reveal to the agent that he wanted to go to Texas to launch an attack.
The latest new trial request focuses heavily on testimony from the agent, who appeared in court under a pseudonym. Prosecutors said the agent's identity needed to be kept secret to protect him and his family and to allow him to continue working undercover.
Kareem's lawyers said the agent interpreted things that Hendricks said to be coded advice on violently attacking the contest. For instance, Hendricks' statement that the agent should make his voice heard against event organizer Pam Geller was really a direction to attack her, Kareem's lawyers said.
The statements demonstrate that the FBI knew much more about the Garland attack than it previously acknowledged or disclosed in Kareem's case.
The agent testified at Hendricks' trial that he didn't know that Simpson and Soofi were going to carry out an attack.
Phone messages left Tuesday and Wednesday for Edward Bryan, an attorney for Hendricks, were not immediately returned.
Hendricks was convicted of conspiring to provide support to the Islamic State and attempting to provide support to the terror group. He faces up to 20 years on each conviction. His sentencing is scheduled for Aug. 8 in Ohio.
He was not charged with participating in the Texas attack.
Follow Jacques Billeaud at twitter.com/jacquesbilleaud. His work can be found at https://bit.ly/2GGWEPO.
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