On the morning of August 20, 1986, a mass shooting occurred at a United States Postal Service facility in Edmond, Oklahoma. Patrick Henry Sherrill, a 44-year-old relief carrier for the post office, entered the building armed with three semi-automatic pistols and extra ammunition concealed in a mail bag. After entering, he locked the doors behind him, trapping employees inside with him.
Sherrill was a relief carrier, meaning he did not have a permanently assigned route and instead worked alternate routes depending on his position on the seniority list, resulting in less job stability than other postal workers. Accounts of his job performance vary: some described him as erratic and irritable, while others said he performed adequately but was subjected to excessive scrutiny from management. On the afternoon of August 19, 1986, the day before the shooting, supervisors Richard Esser Jr. and Bill Bland reprimanded Sherrill for his conduct. Sherrill reportedly threatened revenge twice in response to the discipline.
Shortly after 7:00 a.m. on August 20, Sherrill shot and killed Esser, one of the two supervisors who had disciplined him. He then searched for Bland, the other supervisor, but Bland had overslept and arrived at work an hour late, after the shooting had already ended. Unable to find Bland, Sherrill killed coworker Paul Michael Rockne, the grandson of football coach Knute Rockne, and continued seeking out other coworkers. Approximately 100 employees were in the building at the time. Over the course of less than fifteen minutes, Sherrill killed 14 people and wounded 6 others. The shooting ended when Sherrill fatally shot himself in the forehead as police entered the facility.
Sherrill was born in Watonga, Oklahoma, on November 13, 1941, and had served in the United States Marine Corps. He was described by acquaintances as a loner and was considered an expert marksman, having gained small-arms experience as a member of a pistol team in the Oklahoma Air National Guard.
The Edmond shooting is described as the deadliest workplace shooting in United States history and the deadliest shooting by a lone gunman in the state of Oklahoma. It was among the incidents that gave rise to the American phrase "going postal," and was the first of several highly publicized postal shootings in subsequent years, including incidents in Ridgewood, New Jersey (1991); Royal Oak, Michigan (1991); Dana Point, California (1993); Montclair, New Jersey (1995); and Goleta, California (2006).
A memorial to the victims, the Yellow Ribbon Memorial, was dedicated on May 29, 1989, outside the post office's main entrance. It features a bronze statue of a man and woman holding a ribbon above a fountain with fourteen water jets, one for each victim killed, and a plaque listing their names. The memorial was built through a joint effort of the Edmond community and the United States Postal Service, with the statue created by sculptor Richard Muno.