David Hall went to live with his adoptive parents at 4 years old after being born with fetal alcohol syndrome.

"He was a loving little boy," said his mother, Jacqueline Hall.

After being enrolled in special education while growing up, Mr. Hall attended classes at the Community College of Allegheny County.

Though he didn't drive, he became a prolific bus rider, traveling often from Moon to Downtown.

"He made lots of friends on the buses," Mrs. Hall said.

But on July 20, 2007, as the 24-year-old stepped away from a bus stopped on West Carson Street in the South Side about 11:45 p.m., Mr. Hall was struck by a passing vehicle.

The driver, an off-duty Crafton police officer who had been out to dinner with friends and was headed to a bar, fled the scene.

Two years later, after Pittsburgh homicide detectives received a tip in the case, they arrested Donnie Breeden, 39.

The 17-year veteran police officer, who was terminated shortly after his arrest, pleaded guilty Thursday to leaving the scene of a fatal accident, and no contest to involuntary manslaughter.

As part of a negotiated plea agreement with the Allegheny County district attorney's office, Mr. Breeden must serve the mandatory minimum prison sentence of one to two years in a state facility.

According to Assistant District Attorney Michael Berquist, Mr. Breeden struck Mr. Hall while traveling about 50 to 55 mph and he immediately called his friends, who were in a different car. He told them he thought he hit someone.

When they all gathered at the accident site -- before officers or emergency medical personnel were on scene -- Mr. Berquist told the court on Thursday that the defendant said, " 'I don't know if I hit him or not. I'm a cop. I can't go down for this.' "

Defense attorney William Difenderfer said that his client did not make that statement, but that one of Mr. Breeden's friends suggested he get out of there because he was a cop.

His client and four friends then fled the scene. They went to one of the men's homes in Green Tree to talk about the accident, and in the next days repaired Mr. Breeden's Chevy Trailblazer.

Mr. Breeden continued working as a Crafton officer for two more years. He never turned himself in and was arrested July 3, 2009, after investigators got a tip. None of the others involved in the cover-up were ever charged.

Mr. Difenderfer told Judge Edward J. Borkowski that had his client not fled the scene, he believes there would have been no charges filed.

"He feels extremely remorseful for the victim in this case," he said. "He never saw him coming. This was a pure accident."

Mr. Difenderfer noted that Mr. Breeden stayed on the scene for about 10 minutes before leaving. He said his client was in a panic, but that "the leaving is something he can't take back."

Mr. Breeden, for his part, said only, "I want to apologize for my actions."

Mr. Hall's parents told Judge Borkowski that they consulted with the prosecution about the sentence Mr. Breeden would receive.

"It's not really about us," said Robert Hall, the victim's father. "It's about justice for David.

"Mr. Breeden as a police officer should have known better," Mr. Hall said. "But Mr. Breeden, who knew the law and would have had every expectation to be treated fairly by the law, decided to run away. It would be a shame in running away if he would have succeeded in escaping punishment."

Mrs. Hall spent several minutes describing her son to the court and explained how on more than one occasion, kind police officers had brought him home when he couldn't find his own way there.

"It seemed very strange when we got the knock on the door that David was dead," she said.

Mrs. Hall spoke with regret that because her son was hit not just by Mr. Breeden, but by two cars traveling behind his, his body was so "damaged" that she never got to see him again.

As she concluded her remarks -- after showing Mr. Breeden her favorite picture of her son -- Mrs. Hall said, "I pray you find some kind of way to deal with what's happened and that you find some peace."

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