Maryland's highest court has overturned the murder conviction of a former Army Ranger accused of murdering his roommate.

Attorneys for Gary J. Smith argued that fellow former Ranger Michael McQueen committed suicide in the pair's Gaithersburg apartment on Sept. 26, 2006. Smith's lawyers said a Montgomery County judge shouldn't have excluded testimony from a Georgia police officer who arrested McQueen for drunken driving the month before the soldier's death and said the 22-year-old was upset at that time.

The Court of Appeals agreed, ruling that testimony from Officer John Hegger was relevant to McQueen's state of mind.

Without Hegger's testimony, "the State was able to argue to the jury that there was no evidence of depression or suicidal tendencies from anyone who had come into contact with McQueen," the court's opinion says.

McQueen was found fatally shot in the head a few hours after the two had been out drinking. Smith gave detectives three accounts of what had happened, eventually saying he heard a gunshot as he was leaving the bathroom, touched McQueen's body, panicked and threw the gun into a lake.

Smith, now 29, was convicted of depraved-heart second-degree murder, which is a killing committed while acting in "extreme disregard" for human life. He was acquitted of first-degree murder and intentional second-degree murder and sentenced to 35 years in prison.

Medical examiners testified that McQueen was killed and blood spatter evidence placed Smith near the chair where McQueen was found, according to court records.

But a defense forensic pathologist said the death was suicide, based on the gunshot wound, McQueen's blood-alcohol level, gunshot residue and the lack of apparent motive.

Several of McQueen's friends and relatives said he did not seem depressed. Hegger testified without jurors present and said McQueen "basically appeared to be depressed" at the police station and told the officer that the DWI "is the last thing I need in my life right now."

The appeals court wrote that the testimony "makes it more probable, in conjunction with the opinions of the defense forensic experts, that the defense's ultimate proposition of suicide might be accepted."

Defense attorney Andrew Jezic said allowing that testimony at a retrial will show the jury that McQueen "may have been troubled as a result of his deployment into a combat zone."

A spokesman for the Montgomery County State's Attorney's Office did not respond to a request for comment.