On February 20, 1915, Henry and Mary Ellen Webb, who had married the previous June, began quarreling at their home at 628 Paulson Avenue in Larimer. The quarrel reportedly centered on money. Mary is said to have threatened to leave her husband, an unemployed hotel worker, for another man due to his inability to support her.

When the quarrel escalated the next day, Mary Webb struck her husband with a poker and he responded by slashing her, fatally, with a razor. He then fled the scene. Webb was arrested hours later. He confessed to police and led them to the murder weapon.
Newspaper accounts report that Mary (Fisher) Webb was the daughter of a prominent family and was so well liked that threats of lynching were directed toward Webb when he was arrested.

My research reaches a somewhat different conclusion. Mary was raised in a family of modest means (her father worked as a hod carrier), though she may have experienced the status associated with passing as white (as she is listed on her death certificate, despite being born to Black parents). Indeed, one newspaper account identified her nickname as “The Angel” (Pittsburgh Gazette Times, February 22, 1915).
Henry Webb, who was born in Virginia, was previously married and had a prior assault arrest.
At trial, Webb’s attorney argued that Webb had acted in self-defense and that the evidence justified a manslaughter verdict. He was convicted of first-degree murder on June 18, 1915, and sentenced to death on September 2.
Webb appealed his conviction. In a lengthy appellate opinion (Commonwealth v. Webb, 252 Pa. 187, 1916), his self-defense claim was rejected on the grounds there was no evidence he was injured during the quarrel and no evidence her provocation was sufficient to justify lethal self-defense.

His pardon request also rejected, Henry Webb was executed on May 2, 1916. He is buried in the prison cemetery at Rockview. Webb was the first African American in Pennsylvania to die in the electric chair.