INDIANA, Pa.—A western Pennsylvania man has been convicted of second-degree murder for shooting his estranged wife's father after he intervened in a dispute between the couple last summer.

Thursday's verdict by an Indiana County jury means 33-year-old Shaun Fairman, of Washington Township, faces a mandatory life prison sentence without parole. The sentence will be formally imposed May 28.

Authorities charged that Fairman went to the home immediately after receiving divorce papers although his wife had obtained a protection from abuse order and shot 55-year-old Richard Shotts. Shotts and his wife had been staying at their daughter's home to protect her from Fairman. Jessica Shotts then shot Fairman twice in the shoulder and held him at bay until police arrived.

Fairman's blood-alcohol content was three times the state's limit for legal intoxication at the time.