The first instance of someone "going postal" was on August 20, 1986. Patrick Henry Sherrill was a part-time mail man in Edmond, Oklahoma. He had received a number of disciplinary notices from his supervisors for misdirected mail and customer complaints. He began to suspect he was on the verge of being fired. On August 19th he filed a complaint with his union steward, alleging harassment by his bosses. The next day, he decided not to wait for the union to file the customary grievances. He decided to handle his job grievances with hot lead. He walked into his postal station with three guns (two were 7-shot Colt 45 pistols) and methodically executed 14 coworkers and wounded 6 before putting a bullet in his own head.

Sherrill was described by some as the archetypal "quiet, kept to himself" worker/neighbor. Others knew him as "crazy Pete", a guy who thought the neighbor kids were always laughing at him. He did not mix well with his coworkers. Most found the 44-year old distant and even rude. At previous jobs, a number of women coworkers complained about his sexual harassment, which included him rubbing himself up against women. He was an ex-Marine who, before the killing, was working on his marksmanship skills with the Air National Guard. The ammo and two of the guns he used for his butchery were signed out from the local guard armory.

At that time, Sherrill's postal rampage was the third worst mass murder in US history, eclipsed only by the 21 people James Oliver Huberty bagged in a McDonald's and tying Dead Eye Charles Whitman's body count of 14 (although Whitman tagged 14 from a Texas bell tower... most of Sherrill's victims were blown away at point blank range).

Three years later (almost to the day ... August 10, 1989) John Merlin Taylor shot up his Orange Glen, California postal station. He killed 2 and wounded another before taking his own life. Before his postal rampage he shot his wife.

Then two years later on October 11, 1991, Joseph M Harris was fired from his postal job at a Ridgewood, New Jersey station. He went to the home of his former supervisor and shot her to death plus her boyfriend. He then proceeded to his former place of employment and shot dead two mail carriers in the parking lot as they were arriving from work. Harris, in this case, did not take his own life. He received a death sentence but died while on death row.