James Fields Jr. was acting in self-defense when he drove into the crowd of counterprotesters in Charlottesville last August, his lawyers said in the trial’s opening statements Thursday, following what the judge called the “most complicated jury selection” process he’d ever participated in.

Lawyers representing 21-year-old James Alex Fields Jr., an Ohio resident, said that in the coming weeks, they would argue that their client acted in self-defense on that fateful day in August 2017 because he felt threatened by the protesters at the Unite the Right rally and was in fear of serious bodily injury or death. Fields was among the hundreds of white supremacists and far-right agitators who descended upon the small Virginia college town that weekend, many marching with torches and chanting anti-Semitic slogans, brawling with counterprotesters — and sparking national outrage.

Fields is facing first-degree murder charges for killing 32-year-old Heather Heyer with his car, three counts of malicious wounding, three counts of aggravated malicious wounding, two counts of felonious assault, and one hit-and-run charge. Separately, he’s also facing 29 counts of federal hate crime charges, for which prosecutors have not ruled out pursuing the death penalty.

Earlier on Thursday, a jury of nine women and seven men were seated (12, plus 4 alternates). All but one member of the jury are white; the other is black. Charlottesville Circuit Court Judge Richard Moore, who is presiding over the case, said that it was the “most complicated jury selection” process he’d ever participated in through his 37 years as an attorney and six as a judge. The complication, Moore said, stemmed from the difficulty in finding potential jurors who did not have strong feelings about the violent Unite the Right rally, or of the car attack, which left Heather Heyer, a Charlottesville resident, dead and dozens injured. Her mom, Susan Bro, was in the courtroom Thursday.

Prosecutors will have to prove that Fields acted intentionally and with premeditation when he rammed his vehicle into about two dozen counterprotesters standing at an intersection in downtown Charlottesville on Aug. 12, 2017. In gruesome video footage, which prosecutors plan to rely on heavily, you hear people screaming and see bodies flying. Fields then rapidly reversed, hitting people on the way, and sped off. He was apprehended by a deputy about a mile away and arrested. Earlier in the day, Fields was photographed marching alongside white supremacists, and holding a shield emblazoned with a neo-Nazi group’s logo.

Reporters inside the courtroom say that lawyers offered a preview to the testimony and evidence they plan to present during the trial, including that Fields allegedly idled in his car before he accelerated into the crowd. To prove that the act was premeditated, they also plan to show an post from Fields’ Instagram account shared months earlier, showing a car driving into protesters.

More than 50 witnesses, including people who were injured that day, are expected to testify in the trial, which may last weeks.

Fields isn’t the only participant in Unite the Right to face criminal charges for his actions that day. Three others, Daniel Borden, Jacob Scott Goodwin and Alex Michael Ramos were all found guilty on charges linked to the brutal beating of a black man, DeAndre Harris, in a parking garage during the day’s events.