Chicago’s top federal prosecutor abandoned a closely watched case against four activists who protested outside a federal building during last year’s immigration crackdown, dismissing the remaining charges after a judge scrutinized allegations of grand jury misconduct by the prosecutor’s office, according to court proceedings described by the Associated Press.

U.S. Attorney Andrew Boutros announced the decision to dismiss the remaining charges Thursday after a review of allegations involving grand jury proceedings that are normally secret. The case had been slated to go to trial next week. Perry, a U.S. District Judge, had been examining the misconduct claims in advance of that trial schedule.

Boutros told Perry that he was unaware until recently of the alleged misconduct, which included a claim that a prosecutor met with a grand juror outside of the proceedings. He also cited allegations that jurors who disagreed with dismissing the case were prevented from participating, according to the reporting.

The Associated Press reported that Boutros did not dispute the allegations, saying the conduct was upsetting and that it was the reason the case would be dismissed. Boutros said, “No one acted with the intent to mislead your honor, and I think that they were following your order to give the law,” a line attributed to him in court.

The case arose from protests during the immigration crackdown carried out by the Trump administration, which spread beyond the city into surrounding suburbs. Defense attorneys for the activists, including onetime Democratic congressional candidate Kat Abughazaleh, said they would seek copies of the unredacted grand jury transcripts to understand what they said was misconduct influencing the case.

Abughazaleh’s defense attorney, Josh Herman, said the revelation of the grand jury misconduct “is sadly not surprising,” and he argued that the “misguided case should have never been brought” against Abughazaleh and her co-defendants for exercising what he described as protected First Amendment rights. Herman’s remarks were included in the Associated Press report.

According to the Associated Press, the defendants originally included six people charged in October with conspiracy to impede an officer, a felony. Prosecutors later dropped charges against two of the people, and in a development last month they scrapped the felony conspiracy charge altogether after questions about the grand jury transcripts. Prosecutors’ updated charging documents at that time did not include additional allegations against the activists.

The remaining defendants on the Thursday dismissal were Andre Martin, who was on Abughazaleh’s campaign staff; Oak Park village trustee Brian Straw; and Michael Rabbitt, described as a Democratic committeeperson. Each faced a single misdemeanor count of forcibly impeding a federal agent, according to the Associated Press account.

Perry closed part of a hearing to the public because it involved discussion of grand jury proceedings, which are kept secret. The Associated Press reported that the closure occurred despite objections from the Chicago Tribune, the Chicago Sun-Times and other media outlets.

Perry dismissed the charges with prejudice, preventing prosecutors from refiling. She also floated the possibility of a separate hearing on sanctions for the U.S. Attorney’s Office over its conduct, the Associated Press report said.

The Associated Press said the case was not the first time during the Trump administration that prosecutors faced scrutiny tied to their conduct before grand juries. In another example, a federal judge in Virginia accused the Justice Department of what the judge described as a “disturbing pattern of profound investigative missteps” in securing an indictment against former FBI Director James Comey, including allegations of legal misstatements to the grand jury and transcript irregularities.

As covered by the Associated Press report, the Comey case was later dismissed after a judge determined the prosecutor who filed the false statements prosecution was illegally appointed, and Comey, the Associated Press noted, later faced a newly indicted prosecution related to a social media photo described as a threat.