FORT CARSON, Colo. (AP) -- A soldier accused of repeatedly stabbing another soldier to death in her barracks at a Colorado Army post blames the slaying on a potent mixture of anti-depressants and alcohol.

Fort Carson Sgt. Vincinte Jackson is being court-martialed. He is charged with murder and premeditated murder in the Jan. 6 death of Spc. Brandy Fonteneaux, of Houston. The Gazette reports that the defense Tuesday called forensic psychologist Gail Poyner of Oklahoma City to testify as part of trying to establish whether Jackson intended to kill Fonteneaux.

Poyner quoted studies and research on an anti-depressant that Jackson allegedly mixed with alcohol the night of the slaying. Prosecutors will cross-examine Poyner on Wednesday.

Witnesses also testified that Jackson, who was injured by shrapnel in Afghanistan, was about to retire.