A federal jury on Tuesday acquitted Minneapolis police officer Michael Griffin — accused of violating the civil rights of four men and later lying about it — of most of the charges against him.

Jurors deliberated 3½ days before reaching their decision. They cleared Griffin of the six criminal counts he faced stemming from a brawl outside the Loop Bar in late 2011. But they couldn't reach a verdict on three counts related to a 2010 incident in front of now-defunct Envy nightclub in which Griffin is accused of beating a man unconscious.

Griffin slipped out of the courthouse shortly after the verdict was read, accompanied by his wife and police partner. He has been on home assignment after being relieved of duty shortly after his indictment by a federal grand jury last May.

His attorney, Robert Richman, said Griffin, most recently a patrolman in the Fourth Precinct, was eager to return to the job.

"This is something that has dogged him now for six years," Richman said.

In a statement released shortly after the verdict, U.S. Attorney Andrew Luger said he "strongly believed that this case needed to be brought before a Court, publicly tried, and decided by a jury." He said he was reviewing options concerning the unresolved charges stemming from the Envy incident — one count each of deprivation of civil rights, perjury and falsification of documents. His office declined requests for further comment.

Richman said that the government could still charge his client in connection with the 2010 episode outside Envy, but that he's confident the outcome will be the same.

"They gave it their best shot (but) witnesses were already unable to remember huge portions" of the events, he said.

Mixed verdict

Griffin was indicted last spring on nine counts of perjury, deprivation of civil rights and falsification of records in a federal investigation in connection with the two separate incidents.

In returning a mixed verdict, the jury left the door open for prosecutors to refile three charges in the May 29, 2010, episode outside Envy nightclub. That night, according to prosecutors, Griffin, who was off duty, punched Ibrahim Regai on a crowded sidewalk, knocking him unconscious.

Jurors cleared Griffin of all six charges connected to a separate incident, on Nov. 5, 2011, when prosecutors allege Griffin confronted four men — Jeremy Axel, Matthew Mitchell, Keyon Cooley and another man at the Loop Bar.

During the trial, prosecutors argued that Griffin lied about both incidents — in police reports, to FBI agents and while on the witness stand in lawsuits brought by the men involved in the attacks. The defense argued that it wasn't unusual for an officer involved in a stressful situation to have trouble remembering details.

Police Chief Janeé Harteau released a statement Tuesday, calling the trial a "distraction from the excellent public safety service our officers deliver on a daily basis."

She declined further comment, citing an ongoing internal investigation into whether Griffin committed perjury. The department declined requests to clarify the nature of the internal probe.

Griffin was cleared of wrongdoing by Internal Affairs in one incident and received a letter of reprimand in the other case. He also was found at least partly culpable in two federal lawsuits bought by the men involved in the incidents. A judge ordered the city to pay a combined $410,000 to settle the lawsuits.

The case, which comes at a time when aggressive police tactics are being debated nationwide, has raised questions about whether the department does enough to control officers who, like Griffin, have a history of brutality complaints. While cases of police officers being charged criminally with misconduct are rare around the state, two other Minneapolis officers have been indicted by grand juries in recent years.

Mike Roberts pleaded guilty to corruption and tax evasion charges in 2009 and was sentenced to a year in federal prison following an FBI investigation of corruption in the department. Jason Andersen, a member of the now-defunct Metro Gang Strike Force, was acquitted in 2010 of violating a black teenager's civil rights by allegedly kicking him in the head.

Deliberations at impasse

Throughout the 12-day trial, prosecutors said Griffin was the aggressor and used his position as a police officer to gain an edge in the confrontations. Griffin's attorney argued that his client acted in self-defense when the other men in the Loop Bar incident singled him out because he is an officer and black.

During the trial, authorities issued an arrest warrant for one of the government's witnesses in the Loop Bar incident, who did not show up to testify about his role in the confrontation. The man reportedly told authorities that he no longer wanted to testify against Griffin and that he was worried about losing his job, but later took the stand.

And on Monday, the jury indicated to Judge Donovan Frank that it was at an impasse, with one of the jurors insisting on continuing deliberations. The following day, jurors sent the judge another note, asking about the possibility of returning a verdict on some counts, but not others. Frank responded that they could, but urged them to continue deliberating, according to Richman. Hours later, they filed back into the courtroom to announce their decision.

Libor Jany • 612-673-4064

Twitter:@StribJany