Mark O'Donnell is charged with raping and murdering 14-year-old Ebony Dorsey. She was an honors student at Wissahickon High School and the daughter of O'Donnell's girlfriend.
Prosecutors say O'Donnell did drugs with Dorsey's mother before the killing.
Some of the testimony was so gruesome that some of Ebony's young friends who were at the trial were asked to leave the courtroom.
Last week, the family of Ebony Dorsey had to sit through gruesome testimony about the girl's death and sordid details of her home environment. Much of that testimony coming from her own mother.
Danielle Cattie had just testified that she and her boyfriend Mark O'Donnell spent the last night of Ebony's life snorting and smoking cocaine.
Something, she admits, they did daily for several months.
The night of December 6, 2007 O'Donnell drove Ebony to O'Donnell's Plymouth Meeting apartment to baby sit his four-year old daughter.
He then went back to Cattie's house where, police say, they did cocaine, played backgammon and viewed Internet pornography until about 5:50 in the morning.
O'Donnell then returned to his apartment where, police say, he raped and strangled Ebony. At the time of his arrest, O'Donnell told Action News reporter David Henry he did it.
He also confessed to the police and is now trying to avoid the death penalty.
His lawyer says he was high on cocaine when he just snapped and killed Ebony.
"He was obviously high when he left the house. He was holding a knife while he was playing backgammon because he was so paranoid, and the mother let him leave the house like that to go get her daughter," said defense attorney Thomas Egan.
The prosecutor says O'Donnell knew exactly what he was doing, and it was premeditated.
The defense asked for a bench trial, which means the verdict is up to the judge, no jury. That's because the case is so inflammatory that a jury might be easily swayed to impose the death penalty.
Danielle Cattie has already pleaded guilty to drug charges and charges of endangering the welfare of children.
