The American Civil Liberties Union filed the lawsuit on behalf of the unnamed juror, who wants to be allowed to talk publicly about the case but could face charges for doing so because of a lifetime gag order. The juror also says he or she came away with the impression that evidence was presented differently than in other cases, with the insinuation that Brown, not Officer Darren Wilson, was the wrongdoer.

No grand jurors have spoken publicly about the case.

Brown, who was black, was unarmed when he was fatally shot after an Aug. 9 confrontation with Wilson, who is white. The shooting in the St. Louis suburb led to widespread unrest, including protests that resulted in local business being burned and looted.

Protests again turned violent Nov. 24, when St. Louis County prosecutor Bob McCulloch publicly announced that the grand jury investigating the case had decided there wasn’t enough evidence to indict Wilson. Wilson has since resigned from the department.

“In Plaintiff’s view, the current information available about the grand jurors’ views is not entirely accurate — especially the implication that all grand jurors believed that there was no support for any charges,” the lawsuit says.

The suit was filed against McCulloch, who oversaw the investigation, because his office would be responsible for bringing charges against the juror. McCulloch’s spokesman, Ed Magee, said his office had not seen the lawsuit and declined to comment.

“Right now there are only 12 people who can’t talk about the evidence out there,” ACLU attorney Tony Rothert said. “The people who know the most — those 12 people are sworn to secrecy. What (the grand juror) wants is to be able to be part of the conversation.”

The suit also contends that legal standards in the case were discussed in a “muddled” and “untimely” manner. Jurors could have charged Wilson with murder or manslaughter, but nine of 12 would have needed to agree.

The suit does not seek to allow grand jurors in all Missouri cases to be free to discuss proceedings. But it argues that the Ferguson case was unique, and that allowing the juror to speak would be valuable to the national debate about race and police tactics that followed the shooting.

“The rules of secrecy must yield because this is a highly unusual circumstance,” Rothert said. “The First Amendment prevents the state from imposing a lifetime gag order in cases where the prosecuting attorney has purported to be transparent.”

After the decision was announced, McCulloch took the unusual step of releasing thousands of pages of witness testimony provided in secret to the grand jury. Grand jurors usually hear a condensed version of evidence that might be presented at trial, but the Ferguson grand jury heard more extensive testimony.

The panel — which included nine white and three black members — met on 25 separate days over three months, hearing more than 70 hours of testimony from about 60 witnesses, some of whom provided inconsistent versions of events.