Photo

During the Occupy Wall Street protests and their aftermath, they were the online-video symbols for those who said the New York Police Department was using excessive force:

Deputy Inspector Anthony Bologna, in his white commander’s shirt, walking up to a crowd of people and appearing to pepper-spray protesters at random. And Deputy Inspector Johnny Cardona, who appears to turn around a protester who is walking away and punch him in the face.

Inspector Bologna was found by the Police Department to have violated internal guidelines and was docked 10 vacation days. Both men are facing civil lawsuits in which the city has declined to defend them.

But there will be no criminal charges against either commander, the office of the Manhattan district attorney, Cyrus R. Vance Jr., said Friday afternoon.

“The district attorney’s office has concluded, after a thorough investigation, that we cannot prove these allegations criminally beyond a reasonable doubt,” a spokeswoman, Erin M. Duggan, said in a brief statement. “We have informed the Police Department, the complainants, and the city of our decision.”

A former Manhattan prosecutor, Thomas J. Curran, said that it is harder to prosecute police personnel, particularly for conduct in a chaotic situation like a street demonstration, because using force “is part of their job.”

“The use of force would have to be a complete departure from any legitimate police activity,” said Mr. Curran, who is now a defense lawyer. “You’d have to show an intent to assault, and you have to prove that beyond a reasonable doubt, as opposed to using force as allowed pursuant to police activity. It’s very difficult to do.”

Kaylee Dedrick, one of the protesters pepper-sprayed by Inspector Bologna who has since sued him, said in a phone interview, “Part of me expected that he wouldn’t be prosecuted, but I’m still pretty shocked, with all the evidence against him.”

Her lawyer, Ron Kuby, who represents several protesters who are suing the inspectors, called the decision “cowardly and despicable.”

Prosecutors said they investigated possible assault charges against Inspector Bologna for his use of pepper spray in a protest on East 12th Street on Sept. 24, 2011. In a widely viewed video, Inspector Bologna can be seen striding up to a crowd penned behind orange mesh netting, discharging his pepper-spray canister with a sweeping motion, and walking away.

In the episode involving Inspector Cardona, video shot from several angles on Oct. 14, 2011, appears to show the inspector tapping a man, Felix Rivera-Pitre, on the shoulder, and then, after Mr. Rivera-Pitre turns to look at Inspector Cardona and walks away, the inspector grabbing Mr. Rivera-Pitre and punching him in the face.

The police said at the time that Mr. Rivera-Pitre had tried to elbow Inspector Cardona in the face beforehand and was being sought for attempted assault.

Mr. Curran, who said he had spoken to prosecutors in Mr. Vance’s office about the cases, said that in the case of Inspector Bologna, “he used the spray not specifically at any one person but at the crowd, in response to a situation that’s getting out of control.” The department guidelines Inspector Bologna was found to have violated had to do with using pepper spray in a nonarrest situation without sufficient training, which Mr. Curran said was an entirely different thing from committing assault.

In the Cardona case, Mr. Curran said of Mr. Rivera-Pitre, “the evidence that the D.A. saw suggests that he had his arm cocked in a fist form before Cardona hit him.”

Roy Richter, president of the union to which both commanders belong, the Captains Endowment Association, said that declining to prosecute Inspector Bologna was “the right decision” and that Inspector Cardona had been injured by Occupy protesters and “is the true victim of the O.W.S. fiasco.”

Mr. Kuby said he would ask federal prosecutors to review the cases.