Jurors began deliberations Thursday in the federal assault and perjury trial of Minneapolis police officer Michael Griffin, but with six days of testimony and evidence to ponder, went home without a verdict.

They will resume Friday morning, faced with deciding whether Griffin used his position as an officer to violate the civil rights of four men in separate incidents and then lied about it to FBI agents, as prosecutors allege.

Jurors began deliberating after lunch on Thursday, after hearing closing arguments in federal court in St. Paul from assistant U.S. Attorney Steven Schleicher and Griffin’s lawyer Robert Richman.

In his closing remarks, Schleicher urged jurors to set aside their feelings about the trustworthiness of police officers and instead carefully consider the evidence in arriving at their decision.

Convicting an officer charged with a crime is “harder than you think that it’s going to be,” he told the jury, “because people trust police officers.” He contended that Griffin’s accounts of the incidents were peppered with “magic words to make his actions seem reasonable” in an attempt to shape the narrative surrounding a pair of assaults at downtown hangouts 18 months apart.

Schleicher pointed out that the officer’s assertion that another man came charging at him outside the since-closed Envy nightclub wasn’t seen in surveillance footage that appeared to capture the encounter, and that he kicked an apparently unconscious man in the face during a later episode outside the Loop Bar. In both instances, the government claimed, Griffin tried to cover up his bad acts by filing false police reports painting the other men as the aggressors, and later lying about his role to FBI agents and in videotaped depositions. “He was being a bully with a badge,” Schleicher said.

Griffin didn’t take the stand during the two-week trial. He has denied the allegations.

Richman countered by questioning the credibility of the government’s key witnesses, pointing to inconsistencies in their testimonies as proof they couldn’t be trusted. Race, he said, also played a significant role in the attack outside the Loop Bar.

Griffin, who is black, was surrounded by a mixed-race group of men who were upset after being thrown out of the bar, Richman told jurors. Four in the panel of 14, including two alternates, are African-American. “These two white racists — I’m sorry I have to use that word, but the evidence certainly supports it — were in this alley with an unarmed police officer,” he said of two of the men involved in the November 2011 confrontation.

As in the Envy incident, Richman argued, Griffin felt threatened by the other men and was defending himself.

“Any officer would know that if those two men got to him at the same time, then the situation is dire,” Richman said. “Officer Griffin could not afford to experiment, because if he guesses wrong, he would be beaten.”

Jurors must determine beyond a reasonable doubt whether Griffin was the aggressor in the assaults, as the prosecution has claimed. Richman insists that the other men were the aggressors in the encounters, not his client.

Griffin was indicted last May on nine criminal counts after a yearlong FBI investigation. He has pleaded not guilty to all the charges.