BOSTON (CBS) — Every big city police department walks a fine line when it comes to the use of force, but an I-Team investigation found Boston police may be crossing that line too often.

“It came to the point where I basically accepted that I was going to die.” said Michael O’Brien as he relived a night in 2009 when he allegedly received a beating by a Boston cop that left him brain damaged.

“He wrapped his arm around my neck and it squeezed my trachea, throat area, so much that I had no exchange of air,” O’Brien said. The altercation left him with bleeding in his brain, he said.

O’Brien sued the police and the city and received a $1.4 million out-of-court settlement.

But that’s just one of more than two dozen police misconduct cases settled by the city over the last four years, at a cost of $5.6 million to taxpayers.

The I-Team’s investigation found that figure for Boston tops a list of settlement money paid by other cities with equal or larger populations: Seattle, Washington; Columbus, Ohio; Denver, Colorado; San Francisco, California; and El Paso, Texas.

Boston’s settlement numbers do not include a $3 million payout to the family of David Woodman, a college student who died in Boston police custody in 2008 on the night the Celtics clinched the NBA championship.

“He was attacked from behind and beaten up and slammed down and handcuffed,” said the student’s mother, Cathy Woodman.

The city paid big money before the case even went to court.

“I know why they offered it to us,” Woodman said. “Because they wanted to shut us up. People don’t know the truth. The truth is they’re responsible for David’s death. They took his life.”

Was it police brutality? “Absolutely,” she said.

Boston Police Superintendent Frank Mancini is in charge of professional standards. Despite the settlement numbers, he told the I-Team he doesn’t think the department has a police misconduct problem.

“No, I don’t. Absolutely not,” Mancini said.

Mancini declined to discuss the details of the cases settled by the city, saying those decisions are made at City Hall, not by the police.

“We’re dealing with human beings and we’re dealing with very stressful situations out on the street,” Mancini said. “Any organization can improve and the important thing is we are seeking to improve all the time and to try to get better at what we do.”

We asked former Boston Police Lieutenant Tom Nolan, who served on the force for 25 years, if he thought Boston’s settlement numbers are too high.

“They’re certainly higher than other similarly situated cities,” Nolan said. “Should that be a cause for concern? I think absolutely. I was around for the bad old days, and I know when I was a brand new police officer in 1978 that business was conducted at the end of a night stick and a fist.”

“We’re not there anymore, but it is still is a culture that privileges power and authority and force and we are seeing a slow sea change,” he said.

It’s a sea change too slow for David Woodman’s mother.

“Our son is dead. And that doesn’t ever, that doesn’t go away,” she said.

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