The agent was instead outside a convention center in Garland to show another suspect, who was believed to be a recruiter for the Islamic State, that he could follow his instructions in staging a one-man protest at the anti-Islam event, prosecutors Kristen Brook and Joseph Koehler said in court records filed a week ago.
They say the agent didn't know Elton Simpson and Nadir Soofi, who were killed after opening fire outside the event, were in Texas prior to the attack. "The notion that an undercover agent would knowingly be in proximity to an impending attack involving high-powered rifles while unarmed simply defies common sense," Brook and Koehler wrote.
Attorneys for Abdul Malik Abdul Kareem, who is serving a 30-year prison sentence for providing guns to Simpson and Soofi, as well as other convictions, are seeking a new trial, arguing that authorities withheld key evidence at their client's trial. Kareem is the only person convicted in the attack.
They also say federal authorities didn't reveal until three years after his trial ended that the FBI placed a surveillance camera outside Simpson and Soofi's apartment in Phoenix. The camera was installed on the day they left for Texas.
Kareem, who was in Arizona at the time of the 2015 attack, also was convicted of conspiring with Simpson and Soofi to provide support to the Islamic State terror group. He was one of the first people brought to trial in the United States on charges related to the Islamic State.
Simpson and Soofi were armed with semi-automatic weapons, body armor and had a copy of the Islamic State flag when they arrived at the event near Dallas. They were killed in a shootout with local police officers assigned to guard the event. A security guard was shot in the leg.
Investigators said Kareem had trained Simpson and Soofi on how to use the guns and watched jihadist videos with them. Kareem testified he didn't know his friends were going to attack the contest and didn't find out about the shooting until after they were killed.
The undercover agent had been sitting in a vehicle outside the 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.
The agent's presence at the event, which was publicly revealed months after Kareem's trial had concluded, came to light in a criminal case in Cleveland against Erick Jamal Hendricks, a North Carolina man who was then accused of trying to recruit people to join Islamic State.
Hendricks was later convicted of conspiring to provide support to the Islamic State and attempting to provide support to the terror group. He was not charged in the Texas attack.
Kareem's attorney said Hendricks put the agent into contact with Simpson 10 days before the attack. In one encounter with the agent, Simpson referred to the upcoming contest in Texas.
Prosecutors say the agent's last communication with Simpson occurred nine or 10 days before the attack.
On the day of the attack, the agent communicated with Hendricks while the agent was outside the convention center. Hendricks asked about the size of the crowd, whether snipers were present and other questions, according to records.
A judge who rejected an earlier request by Kareem for a new trial had noted Simpson didn't reveal to the agent that he wanted to go to Texas to launch an attack.
The prosecutors say they didn't become aware of the surveillance camera outside Simpson and Soofi's apartment until this year. They say nothing in the video is relevant to the case and could not have had an effect on Kareem's trial.
In the days after the shooting, then-FBI Director James Comey said federal investigators learned only hours before the contest that a man under investigation for extremist activities might show up and alerted local authorities. Comey also said investigators had no indication that the man planned to attack the event.
Follow Jacques Billeaud at twitter.com/jacquesbilleaud.
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