Less than two weeks until the start of one of the highest-profile murder trials in Georgia history, defense attorneys are trying to exclude what could become a crucial piece of evidence.

The lawyers, representing two men accused of chasing and fatally shooting Ahmaud Arbery early last year in a Glynn County neighborhood, are asking a judge to prohibit photos of a vanity license plate of the old Georgia state flag on the front of Travis McMichael’s pickup truck. Georgia’s prior flag, flown from 1956 through 2001, prominently featured the Confederate battle emblem.

McMichael, his father Greg, who also joined in the motion, and their neighbor, William “Roddie” Bryan, all of whom are white, will stand trial for murder and other charges in the February 2020 death of Arbery, who was Black. Jury selection begins Oct. 18.

The defense’s motion to exclude the license plate, filed last week, calls the evidence “not relevant” and “prejudicial.”

Travis McMichael’s lawyers argue that prosecutors have two goals in submitting the license plate as evidence: “To draw the conclusion that Arbery saw the vanity plate, that he interpreted its meaning and that he feared the occupants in the truck,” prompting him to run; and to infer that McMichael placed the vanity plate on the front of his new truck “in order to telegraph some reprehensible motive, bias or prejudice.”

In their response to the motion, prosecutors argued that McMichael purchased the truck several weeks before the shooting and attached the vanity plate “for all the world to see.”

“The jury may interpret that evidence in any way they deem appropriate and the State may make reasonable inferences, in closing argument, drawn from the evidence,” prosecutors wrote in a subsequent filing urging the judge to allow it.

Arbery, an unarmed 25-year-old, was shot and killed in the Satilla Shores neighborhood just outside coastal Brunswick on Feb. 23, 2020. Travis McMichael, who killed Arbery; his father, Greg McMichael, a former investigator in the local district attorney’s office; and Bryan, their neighbor, were arrested more than two months later after the GBI announced it would look into the case.

Greg McMichael and his son, who were both armed, chased Arbery in Travis McMichael’s pickup truck through Satilla Shores. Bryan soon joined in the chase in his pickup and took the infamous cellphone video that showed Arbery being hemmed in and then charging at Travis McMichael, who killed Arbery with three shotgun blasts.

The McMichaels and Bryan contend they were making a valid citizen’s arrest because they believed Arbery had burglarized a home under construction and was fleeing. Prosecutors say no citizen’s arrest was justified, and they note Arbery, who was running through the neighborhood, had no stolen items in his possession when he was killed.

It is now up to Superior Court Judge Timothy Walmsley to decide whether the photos of the license plate can be shown to the jury. He recently ruled that neither Arbery’s criminal record nor his mental health history can be be brought up by the defense at trial.

When he was in high school, Arbery was sentenced to five years probation as a first offender on charges of carrying a weapon on campus and several counts of obstructing a law enforcement officer. He was convicted of probation violation in 2018 after he was charged with trying to shoplift a television from a Walmart, court documents show.

Arbery was on probation when he was killed, but prosecutors on Monday filed a motion to exclude the defense from bringing that up at trial, saying “his status as a probationer is not relevant, as the defendants did not know Mr. Arbery was on probation.”

Last week, Walmsley ruled a nurse’s “highly questionable diagnosis” that Arbery suffered from mental illness could unfairly prejudice the jury. The rulings are a blow to the defense, and could hinder their efforts to portray Arbery as the aggressor.

The deadly shooting prompted the Georgia Legislature to overhaul the state’s Civil War-era citizen’s arrest law. It was the second piece of criminal justice legislation to become Georgia law in the wake of Arbery’s death. Lawmakers also passed hate-crimes legislation in 2020, increasing penalties for those convicted of committing crimes against people based on characteristics such as their race, sexual orientation or religion.

Marietta defense attorney Ashleigh Merchant, who has been closely following the case, said she agrees with Walmsley’s decision to exclude Arbery’s mental health history, saying defense attorneys for Bryan and the McMichaels would have had to show their clients were aware of his previous diagnosis.

“If they didn’t know about that at the time, I don’t see how it’s relevant,” she said Wednesday.

By trying to exclude evidence of Travis McMichael’s vanity plate, the McMichaels’ defense team is trying to make it tougher for prosecutors to establish racial bias, Merchant said, adding they need to “humanize their clients” in an attempt to get the jurors to look past any history of racism that will undoubtedly be brought up by the state at trial.

“We all know that the trial is going to be an issue of whether or not these folks were racist,” she said.

Separately, the U.S. Justice Department has obtained a hate-crimes indictment against the McMichaels and Bryan, alleging they chased and tracked down Arbery because he was Black. That case is set to go to trial in February.

According to pretrial testimony, Bryan told GBI agents after the shooting that he heard Travis McMichael say “(expletive) N-word” as he stood over the dying Arbery. McMichael has denied saying that.

— Staff writers Bill Rankin and Asia Simone Burns contributed to this article.