Going postal

Going postal, in American English slang, means becoming extremely and uncontrollably angry, often to the point of violence, and usually in a workplace environment.

The expression derives from a series of incidents from 1986 onward in which United States Postal Service (USPS) workers shot and killed managers, fellow workers, and members of the police or general public in acts of mass murder. Between 1986 and 1997, more than 40 people were gunned down by current or former employees in at least 20 incidents of workplace rage.

In Australia, the phrase is used in reference to the Queen Street massacre in 1987, in which gunman Frank Vitkovic murdered eight people inside an Australian Post office building in Melbourne.

The earliest known use of the phrase was on December 17, 1993, in the St. Petersburg Times:

The symposium was sponsored by the U.S. Postal Service, which has seen so many outbursts that in some circles excessive stress is known as 'going postal.' Thirty-five people have been killed in 11 post office shootings since 1983. The USPS does not approve of the term "going postal" and has made attempts to stop people from using the saying. Some postal workers, however, feel it has earned its place.

On December 31, 1993, the Los Angeles Times stated:

Unlike the more deadly mass shootings around the nation, which have lent a new term to the language, referring to shooting up the office as "going postal".

On August 20, 1986, during the Edmond post office shooting, 14 employees were shot and killed and 6 were wounded at the Edmond, Oklahoma, post office by Patrick Sherrill, a postman who then committed suicide with a shot to the forehead.

A former United States postal worker, Joseph M. Harris, killed his former supervisor, Carol Ott, and killed her boyfriend, Cornelius Kasten Jr., at their home. The following morning, on October 10, 1991, Harris shot and killed two mail handlers, Joseph M. VanderPaauw, 59, of Prospect Park, New Jersey, and Donald McNaught, 63, of Pompton Lakes, New Jersey, at the Ridgewood Post Office.

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