"This was a difficult and troubling case," he said.

He explained his decision to decline prosecution by saying that after a review, prosecutors believed they would have insufficient evidence to prove criminal charges beyond a reasonable doubt. To earn a conviction on a federal criminal civil rights charge, the government would have to show that the officers "willfully deprived" Mr. Miles of a constitutional right.

"Proving 'willfulness' is a heavy burden and means that it must be proven that the officer acted with the deliberate and specific intent to do something the law forbids," the Justice Department said in its statement. "Neither negligence, accident, mistake, fear, nor bad judgment is sufficient to establish such a criminal violation."

Mr. Miles' attorney, J. Kerrington Lewis, was disappointed by the decision. He called it "ridiculous."

"I disagree with their assessment that they don't have a case to prove they'd be guilty beyond a reasonable doubt," Mr. Lewis said. "The findings are simple and straightforward."

He acknowledged that the decision not to prosecute is fully within the discretion of the Department of Justice, but said, "It should have been decided by a criminal jury."

Mr. Lewis' attention will now turn squarely to a federal civil rights lawsuit he filed on Mr. Miles' behalf. That case is still moving through the court system, with the discovery phase of the case scheduled to end in September.

Attorneys for the officers said their clients are relieved but frustrated that the decision was such a long time coming. Through their lawyers, the officers declined comment.

"They did nothing wrong," said Bill Difenderfer, who is representing Officer Saldutte. "It has affected their morale, and for good reason. [They] were trained and told to be proactive and then everyone turns their back on [them]. ... These guys were held in limbo. They couldn't leave or get a job with another department with this cloud over their heads. It's tremendous, and it's a huge sigh of relief, but the question now is, how are they going to be treated by the department?"