FLORENCE, Ariz. -- The death of a convicted Arizona serial killer whose body was discovered last month in an isolation cell was ruled a suicide Thursday by a medical examiner who said the gunman who once terrorized Phoenix had overdosed on antidepressants.
Dale Hausner, 40, was found guilty in a series of random shootings on pedestrians, bicyclists and animals. The former airport janitor was given six death sentences and hundreds of years in prison for killing six people and attacking 19 others in 2005 and 2006.
Hausner was found unresponsive June 19 in his cell at the Eyman state prison complex in Florence. He was pronounced dead about an hour later at a hospital in Anthem, according to Arizona Department of Corrections officials.
Forensic pathologist Dr. Gregory Hess, of the Pinal County Medical Examiner's Office, said the cause of death was "amitriptyline intoxication." Amitriptyline is one of a variety of antidepressant medications.
Prison officials said it wasn't immediately clear how Hausner obtained the antidepressants. DOC officials said the department was conducting a complete investigation into the circumstances of Hausner's death and the autopsy report was part of that probe.
Hausner always denied any involvement in the attacks and suggested his former roommate might have carried out some of the crimes.
Hausner was arrested in August 2006 with his roommate Sam Dieteman at the apartment they shared in the Phoenix suburb of Mesa. Inside, police found guns, news clippings of the killings and a city map marked with the locations of some of the shootings.
Dieteman, who pleaded guilty in two of the killings and was sentenced to life in prison, testified against Hausner, saying they cruised around late at night looking for strangers to shoot.
The "serial shooter" attacks and an unrelated serial killer case kept neighborhood watch groups on high alert in the summer of 2006. Families stayed inside and authorities called meetings that drew hundreds of people.
Police said their big break came when one of Dieteman's drinking buddies called police to say Dieteman had bragged about shooting people.
Even though Hausner had denied any involvement, he took an odd turn during the penalty phase of his trial when he apologized to the families of every victim.
Since his convictions, Hausner had asked that he be executed quickly.
County authorities have said that while he was awaiting trial, Hausner tried to kill himself with an overdose of cold tablets.