PITTSBURGH (KDKA) — A Baldwin man has pleaded guilty but mentally ill to third degree murder in the 2018 stabbing and shooting death of his roommate while the pair were living in Carrick.

The plea will allow 37-year-old Joseph Martin to serve his prison term with mental health treatment.

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Joseph Martin (Source: Pittsburgh Department of Public Safety)

Police found the victim, 71-year-old Ricardo Tobia, and his dog, dead inside the Carrick home on Kirk Avenue in July of 2018.

Both were shot in the head and had their necks slashed. Tobia was found nearly decapitated.

Tobia was a voice instructor at Point Park University for 35 years.

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ricardo tobia, carrick homicide victim, sparky tobia

Ricardo Tobia and his dog Sparky (Source: Facebook)

Following the murder, Martin was committed to Jefferson Hospital Psychiatric Ward involuntarily.

Martin’s mother told investigators in 2018 that she had been looking in her son’s car when she found a gun and a box of bullets. She also said she removed dirty clothes from the car and washed them.

Police said there were apparent blood smears on the box of bullets and seven bullets were missing from the tray of 50.

Police say they also found Martin’s blood-stained shoes in his parent’s basement, under the coffee table. The tread pattern on the bottom of the shoes was consistent with the bloody shoe impressions found in the dining room of the home where the murder occurred.

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Martin will be sentenced on Sept. 8.