Hennepin County’s top prosecutor has convened a grand jury as he weighs whether to charge a Minneapolis police officer in the July police shooting of an Australian woman, attorneys said Wednesday, just a month after he pushed back a charging decision and said more investigation was needed.

County Attorney Mike Freeman declined to confirm the grand jury, citing the secrecy of any such proceeding, but said he still intends to make his own decision on whether to charge the officer.

Justine Ruszczyk Damond, a 40-year-old life coach, was killed by Minneapolis officer Mohamed Noor just minutes after she called police to report a possible sexual assault in the alley behind her home in Southwest Minneapolis. Noor hasn’t been charged, and Freeman said weeks ago that more investigating was needed in the case. He also told activists in a recorded conversation that he didn’t have enough evidence and investigators “haven’t done their job.”

The attorney for Matthew Harrity, Noor’s partner on the night of the shooting, told the Star Tribune that Harrity got a grand jury subpoena Wednesday. Attorney Fred Bruno told the newspaper the subpoena was a surprise.

Lt. Bob Kroll, the police union president, said in a statement that officers were being issued subpoenas. He said they would cooperate.

In recent years, Freeman has said he would no longer use grand juries to decide whether officers would be charged in police shootings, saying he would make those decisions himself to provide more accountability and transparency.

Grand juries can be helpful in investigations because they can subpoena witness testimony and other evidence in a case. But they are typically used in state court to make charging decisions. Lying before a grand jury can result in perjury charges.

Marsh Halberg, a criminal defense attorney who is not connected to this case, said it could give Freeman a strategic advantage by requiring witnesses to testify under oath and lock down witness testimony in advance of a possible trial. Still, Halberg said, it’s unclear whether a grand jury can be used strictly for investigative purposes on the state level, and it’s not something he has seen in his 40-year career.

Halberg said Freeman could be using the grand jury as “a tactical reason to get evidence from people who are maybe refusing to testify.”

Robert Bennett, an attorney for the Damond family, said he and the family support Freeman’s use of the grand jury and think it’s the right thing to do. Bennett said it’s disappointing that subpoenas were necessary to get witnesses, including police officers, to be truthful.

“This is a very unique procedure to have to use, but we applaud it,” Bennett said.

Noor’s attorney, Thomas Plunkett, issued a statement saying Freeman’s comments “leave me unclear as to what he is doing.” He added that “it would be unethical and potentially unlawful to comment publicly on this development. Worse — any public comment would jeopardize the fairness of an important judicial function.”

Noor has not spoken publicly about the case and has declined to speak with state investigators.

Harrity, Noor’s partner, has told investigators he was startled by a loud noise right before Damond approached the driver’s side window of their police SUV on July 15. Harrity, who was driving, said Noor then fired his weapon from the passenger seat, shooting Damond.

Damond, who was unarmed, died of a gunshot wound to the abdomen.

The officers didn’t turn on their body cameras until after the shooting, and there was no squad-car camera video of the incident. The lack of video was widely criticized as the case gained international attention. The shooting also prompted questions about Noor’s training and led to the city’s police chief ultimately being fired.

The grand jury process has been criticized for its secrecy and because it rarely results in charges against officers. Freeman broke precedent with the standard practice of using grand juries to decide charges in police shootings after the November 2015 death of Jamar Clark. Freeman noted at that time that grand juries had been used to consider police shootings in his county for more than 40 years and no officers had been indicted.