Derrick Powell, 24, of Cumberland, Md. was convicted last week in the September 2009 shooting of patrolman Chad Spicer, 29. Powell faces either the death penalty or life in prison without the possibility of parole.

Powell wiped his eyes with a tissue as he heard testimony from his mother, Tina Durham, and father, Joseph Powell, who were called as witnesses by defense attorneys hoping to spare Powell from execution. As Powell turned to bailiffs to be handcuffed and led from the courtroom during a break in the hearing, his eyes were red and glistening.

Powell’s parents offered sometimes conflicting accounts of his childhood, but both testified that they physically and verbally abused him, even as they spent years working with counselors and social workers to figure out how to deal with his angry outbursts and frequent discipline problems, both at home and at the many schools he attended before he dropped out at age 15.

“Joe and I butted heads a lot about Derrick and how to discipline,” Durham said.

Joseph Powell recalled how he once was called to his son’s elementary school and arrived to find several teachers sitting on the boy’s arms, legs and chest on the stairs outside.

“His face was blue. It was a dark, dark, blue,” Powell said. “I said … get off him, he can’t breathe.”

Powell said he regretted his opposition to giving his son anything but the bare minimum of the psychiatric drugs that doctors had prescribed for him. Powell said he had wanted to prevent his son from falling prey to the same drug abuse that he had engaged in.

“I apologize to you, my son, for not taking more on an interest in it,” the elder Powell said, glancing at his only son.

“I kept those things away from him not knowing that this kid needed to be on medication for the rest of his life,” Powell explained under cross-examination by prosecutor Paula Ryan.

But Powell challenged his ex-wife’s suggestion that it was his decision not to place their son in a psychiatric facility for an intensive mental health evaluation.

“That conversation never happened,” he said.

Durham, who said Derrick Powell was born six weeks prematurely after her placenta ruptured, testified how she bit her 8-year-old son hard enough to leave a large bruise on his arm after he chomped down on her finger as she was giving him a bath.

“I gave him a bruise, and I still have a scar from when he bit me,” she said.

That incident led social service officials in Allegany County, Md., to give permanent custody of Powell to his father, who testified that he punched his son in the face during an argument shortly before his 18th birthday.

“He was very out of control,” Durham said. “He got kicked out of kindergarten for his behavior, and it escalated from there.”

Even Powell’s 78-year-old grandmother took a swing at him when he began arguing with his stepmother during a visit, Joseph Powell said.

“She punched him in the eye and left a mark,” he said.

Powell, who testified that both he and his wife used marijuana and crack cocaine, said they were physically abusive to each other, a trait that seemed to be inherited by their son.

“He could be sitting down eating a bowl of ice cream one minute, and the next minute he was throwing the bowl across the room,” he said.

(Copyright 2011 by The Associated Press. All Rights Reserved.)