On September 11, 1969, while serving time for rape at the Allegheny County Workhouse in Blawnox, Hoss and another inmate escaped. Hoss soon began a spree of murderous violence that prompted a huge FBI manhunt. During the spree, Zanella pulled over Hoss for speeding near Oakmont Country Club. Hoss shot Zanella as the officer approached his car.
Hoss then fled to Maryland, where he kidnapped a 21 year old woman, Linda Peugeot, and her infant daughter. He killed both of them and fled west. Hoss was captured in Waterloo, Iowa, when spotted driving Peugeot’s car. He confessed to all three killings.
Hoss was found guilty and sentenced to death in March 1970 for Zanella’s murder. On appeal, on October 12, 1971, the Pennsylvania Supreme Court reversed his death sentence due to inappropriate use of his prior record when considering his penalty. He was sentenced to life.
On December 10, 1973, Hoss and two other inmates killed Captain Walter Peterson, a black prison guard, at Western Penitentiary. During the beating, the attacking inmates shouted racial slurs at Peterson. With the death penalty having been ruled unconstitutional, the murder of a prison guard by a formerly death sentenced prisoner sparked considerable controversy about deterrence.
Stanley Hoss committed suicide in prison on December 6, 1978.