Prosecutors in the trial of Donte Johnson, accused in the June 2010 strangling death of Sabina Rose O'Donnell, concluded presenting their case this morning in Common Pleas Court.

Attorneys for Johnson, 20, expect they will finish presenting their defense by the end of today. Johnson will not take the stand, his lawyers said.

The main witness to be called in Johnson's defense will be Gerald Cooke, a neuropsychologist who is expected to testify as to Johnson's mental capabilities. Cooke recently performed a battery of tests on Johnson over a two-day period, and is expected to testify that Johnson suffers from mental dysfunction.

Earlier today, Johnson's lawyer, Gary Server, sought to highlight potential weaknesses in the confession Johnson made to police shortly after the murder. Johnson admitted to putting O'Donnell in a choke hold, said he could not breathe and became unconscious.

"You never asked Donte Johnson if he killed Sabina O'Donnell?" Server asked Philadelphia Det. Thorsten Lucke, who interviewed Johnson.

"In not so many words, but I believe he did," Lucke said.

He testified that Johnson was "evasive" when asked how O'Donnell's bra ended up knotted around her neck, saying that he did not seem willing to go into detail regarding her many injuries.

Server also questioned some of the language used in the police statement, asking Lucke if Johnson really used words like "ejaculated" when he referred to O'Donnell's rape.

"Yes, but he mispronounced the word," Lucke said.

Contact Allison Steele at asteele@phillynews.com. Follow on Twitter @AESteele.