John Tiernan and Patrick Campbell, fellow Irish immigrants, lived and worked together in Turtle Creek. Campbell had a contract to build a mile of the Pittsburgh and Greensburg Turnpike. Tiernan, a middle-aged man who left behind a family in County Kildare (and, reportedly, another in New York and a third in Philadelphia), subcontracted from him.
On December 7, 1817, a year and a half after beginning their work together and a few days after Campbell received a large cash advance for his work, Tiernan killed him with an axe and buried his body under the floorboards of their cabin. Tiernan fled, taking Campbell’s horse and other of his possessions. He was arrested in Westmoreland County on December 11, after suspicious neighbors found Campbell and began a search for Tiernan.
After being indicted on January 15, 1818, Tiernan was tried, convicted after fifteen minutes of deliberation, and sentenced to death on January 17, just six weeks after the killing. In the absence of eyewitnesses, the case against Tiernan was circumstantial, though the chain of events pointed clearly to his responsibility. His execution was set for March 25, 1818.
On that day, Tiernan was conveyed by cart to the gallows at Boyd’s Hill, guarded by city militia and with a long public procession in tow. A crowd estimated in the thousands watched an event so momentous in the city’s history that it was used for years to mark time. Almost exactly twenty-five years since Dunning’s execution, Tiernan became the second and last person to be publicly hanged in Allegheny County.
Already forgetting the short history of the newly formed city, the Pittsburgh Weekly Gazette wrote that “it was the first scene of the kind ever witnessed in this part of the country, since civilized men have occupied the soil” and that “eight or ten thousand persons were present.” Tiernan was buried under the gallows.
In the manner of the day, an abridged version of the trial and of Tiernan’s confession was published soon after the events.
The turnpike connecting Pittsburgh and Harrisburg, a much needed route over the Allegheny Mountains, opened on May 20, 1818.
Moved by the spectacle of large crowds and disorderly displays at hangings across the state but unable to achieve abolition legislatively, on April 10, 1834, the Pennsylvania General Assembly passed an “act to Abolish Public Executions.” This compromise, understood as a partial abolition, moved hangings from a public locale to within the confines of the jail in the county in which the sentence was imposed.
Pennsylvania was the second state to make this change.* Rhode Island had banned public executions in 1833. It would be more than a century before Missouri followed suit, ending public executions in the United States.
* Between 1682-1834, 252 public executions were recorded in Pennsylvania, including two in Allegheny County.