CENTENNIAL, Colo. (AP) -- A police officer responding to the deadly Colorado theater shooting testified Tuesday that he asked James Holmes twice whether he had an accomplice, but Holmes only looked at him and smiled.
Officer Justin Grizzle (GRIZ'-uhl) described the smile as "a self-satisfying offensive smirk" during a pretrial hearing over Holmes' statements to police before he was read his Miranda rights.
Grizzle and officer Jason Sweeney were among the first officers to arrive at the back exit to the theater on July 20, 2012, and found Holmes standing beside his car. It was a chaotic scene with screaming and bloodied victims still fleeing the theater as officers handcuffed Holmes and searched him.
Sweeney said that when he asked Holmes if there was another shooter, Holmes answered "No, it's just me."
Other officers have testified that they asked Holmes the same question without realizing he had already been asked.
"It was just chaos with everybody trying to figure out what was going on," Sweeney said.
Roughly two hours would pass before the confusion subsided and detectives would read Holmes his rights -- anything you say can be used against you. In the meantime, officers also asked Holmes questions about weapons and explosives.
Holmes' lawyers argued in written briefs that the delay violated his constitutional rights and that anything he told the arresting officers should be barred from his trial.
In court Tuesday, they also argued that because Holmes said nothing at the same time he allegedly smirked at Grizzle, his response was silence, and a suspect's failure to answer an officer's question can't be used as evidence by the prosecution.
"This was nothing more than silence, and it should be analyzed as such," defense lawyer Kristen Nelson said.
Prosecutors argued that the officers urgently needed to know whether Holmes had an accomplice who could still be shooting and killing people at the Century 16 theater in Aurora. They contend that the questions were legal under a public-safety exemption to the Miranda rule.
Prosecutor Karen Pearson called the alleged smirk "a nonverbal statement that meant something" and said it should be admissible at Holmes trial. She said later it was "a statement of satisfaction" with the shootings.
Dan Recht, a longtime Denver defense attorney who is not involved in the Holmes case, said the Holmes' lawyers view the alleged smirk as unfairly prejudicial to their case.
"The smirk itself is arguably not relevant at all to the issue of Holmes' sanity," Recht said.
The judge didn't say when he would rule on the issue.
Barring the officers accounts of the alleged smirk and Holmes' answers to them would likely have a limited impact on his trial because his lawyers have acknowledged he was the shooter and the trial is expected to focus on whether or not he was legally insane at the time of the shooting.
Holmes is accused of slipping into a suburban Denver theater and opening fire on more than 400 people who were watching a midnight showing of a Batman movie. Twelve were killed and 70 injured.
Holmes, then 24, had just quit a Ph.D. program in neuroscience at the University of Colorado, Denver.
He pleaded not guilty by reason of insanity to more than 160 counts of murder and attempted murder. His lawyers say he was in the grip of a psychotic episode.
Prosecutors are seeking the death penalty.
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