St Louis - A member of the grand jury that declined to indict a Ferguson, Missouri, police officer in the shooting death of an unarmed 18-year-old black man has filed a lawsuit on Monday, claiming that the prosecutor in the case has wrongly implied that all 12 jurors believed there was no evidence to support charges.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 the slain man, Michael Brown, not Officer Darren Wilson, was the wrongdoer. No grand jurors have spoken publicly about the case.Brown was fatally shot after a confrontation with Wilson, who is white, on 9 August. The shooting in the St Louis suburb led to widespread unrest, including some protests that resulted in local business being burned and looted. Protests again turned violent on 24 November, 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.The suit was filed against McCulloch, who oversaw the investigation, because his office would be responsible for bringing charges against the juror. McCulloch's spokesperson, Ed Magee, said his office had not seen the lawsuit and declined immediate 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.