BY MEREDITH DELISO AND JULIA JACOBO, ABC News

(ROCHESTER, N.Y.) — An independent investigation into the government handling of the death of Daniel Prude moved forward on Friday when the Rochester City Council authorized the power to subpoena several city departments, including Mayor Lovely Warren’s office and the Rochester Police Department.

The City Council voted 8-0 during a special virtual meeting Friday morning to authorize the subpoenas, which support an “independent investigation into the internal communications, processes and procedures that took place related to the death of Daniel Prude” and grants authority to “investigate all city departments including the right to review records and papers” and issue subpoenas.

City Council President Loretta Scott said the investigation would start with the first 911 phone call placed on March 23 regarding Prude, 41, a Black man who died a week after being restrained by Rochester police during a mental health emergency.

Andrew G. Celli Jr., an attorney with the New York law firm Emery Celli Brinckerhoff Abady Ward & Maazel LLP, will lead the independent investigation, which the City Council approved on Tuesday.

“[Rochester] is a community that’s asking hard questions and it’s a community that deserves clear answers,” Celli said during a media briefing Friday after the City Council’s vote. “And that’s what I’m committed to do.”

The investigation will look to determine “who knew what when” in the death of Prude, Celli said. “There’s really one question here, and that is: Was there a cover-up? That’s a blunt way to put it, but that’s the question we are seeking to answer.”

The team plans to gather sworn testimony from witnesses, emails, text messages, memos and other documents as it seeks to determine a timeline of events, examine how city departments communicated with each other behind closed doors, and what city officials said publicly, versus what they knew at the time, Celli said.

Celli acknowledged that some of these documents have already been released in a 300-plus-page report commissioned by Rochester Deputy Mayor James Smith, which includes police reports and emails.

“We’re going to go much deeper than the deputy mayor did, and we’re going to get to the bottom of this,” Celli said.

His team plans to issue subpoenas to four Rochester agencies — the mayor’s office, the police department, the law department and the City Council — by Monday, Celli said. They haven’t decided whose testimony they will take, though Celli said that the mayor is under consideration.

The investigation should take about three months, at which point they will release their report to the public, including transcriptions of collected testimonies, Celli said.

The intragovernmental study is one of several investigations stemming from Prude’s death, including one from his family, who has alleged an internal cover-up in a federal lawsuit against the city. The state attorney general’s office also has moved to empanel a grand jury, which would determine whether criminal charges should be brought in the case, as part of its investigation.

On Monday, Warren announced she would enact several reviews from the deputy mayor’s report. She has called for the City Office of Public Integrity to initiate a thorough investigation to determine if any employees, including herself, violated city policies or ethical standards, and she called on the U.S. attorney general to investigate whether Prude’s civil rights were violated.

Earlier this month, police body camera footage was released showing the incident between the officers and Prude. In the video, officers are seen pinning Prude to the ground while a spit bag is on his head, and he eventually appears to go unconscious. Prude died a week later. The Monroe County medical examiner listed his death as a homicide caused by “complications of asphyxia in the setting of physical restraint.”

Seven officers involved in the incident have been suspended as the state attorney general conducts her investigation. On Monday, Warren also fired Rochester Police Chief La’Ron Singletary, two weeks before he was set to retire, amid shakeups in the department.

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