Patrick Sherrill – The Edmond Post Office Massacre
Introduction
On August 20, 1986, 44-year-old Patrick Henry Sherrill walked into the U.S. post office where he worked in Edmond, Oklahoma, and in less than 15 minutes turned it into one of the deadliest workplace massacres in American history. He moved through the sorting area with three handguns, systematically shooting coworkers and supervisors, killing 14 and wounding 6 before turning a pistol on himself. The slaughter shocked the country and helped cement a new phrase into the language of violence and work: “going postal.”
Early Life and Work History
Patrick Sherrill was born in 1941 and grew up in the Oklahoma City area, described in contemporaneous reporting as a socially awkward, introverted boy who struggled to connect with peers. He served in the U.S. Marine Corps and later in the Oklahoma Air National Guard, where he gained training with firearms and was considered a competent, if unremarkable, serviceman. After leaving active military service, he bounced between jobs before landing at the U.S. Postal Service as a part-time letter carrier in Edmond, a growing suburb north of Oklahoma City.
At the post office, coworkers knew him as “Crazy Pat” – a nickname that reflected his odd, sometimes volatile demeanor. He lived alone, never married, and spent much of his off time engaged in amateur radio (he held a ham radio license) and target shooting at local ranges. Supervisors and colleagues described him as moody, defensive about criticism, and rigid about routines, yet also capable of performing his route competently when he chose. He was a “probationary” employee, not yet fully permanent, which heightened his sensitivity to any hint that his job was at risk.
Escalation and Warning Signs
In the months leading up to the massacre, Sherrill’s behavior reportedly grew more tense and erratic. Coworkers later told investigators that he was increasingly angry about management practices, workload demands, and what he experienced as nitpicking over his performance. The Edmond facility, like many postal installations at the time, was under pressure for efficiency and discipline; the 1987 Postal Service report on the massacre noted that supervisors used strict monitoring and “paperwork harassment” that many employees found demoralizing.
Sherrill stood out even within that stressful environment. He had received multiple warnings about his performance and attendance and had a history of conflicts with supervisors. On August 19, 1986 – the day before the shooting – he was formally reprimanded by two supervisors for poor performance on his route, including customer complaints about misdelivered mail. Witnesses reported that he reacted with visible anger, and one supervisor allegedly told him they would “discuss [his] future” the next day, which Sherrill seems to have interpreted as a signal that he would be fired.
Coworkers had long been uneasy around him. Some described him as a “loner” who glared when corrected, and others recalled dark jokes that he might one day “come back shooting,” a line that in hindsight reads as an ignored warning more than gallows humor. He had a known fixation on guns, owned multiple pistols, and was a regular at shooting ranges. Yet there is no indication that anyone elevated their concerns beyond informal talk; no structured threat assessment or mental-health referral was made before he snapped.
Timeline of the Edmond Post Office Attack
In the early hours of August 20, 1986, Sherrill put his private plan into motion. He arrived at the Edmond post office just before his shift, carrying three semi-automatic handguns – two .45-caliber pistols and a .22-caliber pistol – along with extra magazines and ammunition. At approximately 7:00 a.m., as workers were sorting mail and preparing their routes, he pulled his weapons and began shooting.
His first targets were supervisors and coworkers near the sorting cases. Witnesses described him moving quickly and methodically through the workroom area, firing at close range at people he appeared to recognize and, at times, shooting individuals multiple times as they lay on the floor. Some victims seemed to be singled out – including at least one of the supervisors who had reprimanded him the previous day – while others were caught in his line of fire as they tried to flee or hide.
The workroom floor, with its long rows of sorting cases and limited exits, became a trap. Several employees managed to escape through dock doors or side exits, running to nearby businesses to call police. Others barricaded themselves in restrooms or behind equipment. Sherrill continued firing in short bursts, moving among the cases and shooting anyone he encountered, reloading as needed.
Police received emergency calls around 7:05 a.m. and arrived within minutes, but by the time tactical units were ready to enter, Sherrill’s rampage had largely run its course. Gunfire inside the building ceased around 7:12–7:15 a.m. When officers finally made entry, they found 14 employees dead or dying and 6 wounded, scattered across the workroom floor. Sherrill himself was found dead from a self-inflicted gunshot wound to the head, lying near his workstation with his pistols nearby.
Psychological Autopsy
Because Sherrill died at the scene and left no manifesto, any psychological analysis is reconstructive, based on interviews, records, and the Postal Service’s internal report. Overall, his profile matches what would later be recognized as a “classic” workplace mass shooter: a socially isolated, grievance-laden middle-aged man, with rigid thinking, poor coping skills, and access to firearms, who fixated on perceived humiliation by supervisors.
Neighbors and coworkers described him as “never happy with the world or himself,” a man who seemed perpetually resentful and sensitive to slights. He had limited social support – no spouse or close friends – and his identity was heavily bound up with his job and his sense of being competent. When supervisors challenged that image through reprimands and performance reviews, he experienced it as a profound threat to his self-worth.
The 1987 Postal Service report emphasized that while Sherrill may have had underlying psychological issues – including possible depression, paranoia, and rigid, obsessive traits – there was no clear record of diagnosed mental illness or treatment. He appears to have been a classic “injustice collector,” storing up every perceived wrong and insult, replaying them mentally, and gradually shifting from simmering anger to a desire for violent revenge.
Unlike some later mass shooters, there is little evidence of ideological motivation, fame-seeking, or an elaborate fantasy life beyond the context of his workplace. His target selection – almost exclusively coworkers and supervisors, in his place of employment, during work hours – points to a narrow, focused rage: this was payback against the people and institution he believed had mistreated and humiliated him. The rapid suicide once his killing was complete suggests he saw the attack as a one-way trip, a final act of control in a life he felt had spiraled beyond his grasp.
System Failures and “Going Postal” Legacy
In the aftermath, the Edmond massacre prompted intense scrutiny of USPS management practices, workplace culture, and how organizations handle troubled employees. The Postal Service’s own report acknowledged a “climate of fear” at the Edmond facility, with heavy emphasis on discipline, production quotas, and written reprimands, and insufficient attention to communication, conflict resolution, and employee well-being. Supervisors were criticized for their handling of Sherrill – particularly for delivering sharp reprimands without considering his history of volatility and social isolation – though the report stopped short of assigning direct blame for his actions.
The event also marked a turning point in the cultural understanding of workplace violence. The phrase “going postal,” which had its origins in media and stand-up comedy referencing postal shootings, gained traction in the years after Edmond as more workplace incidents occurred, including subsequent USPS shootings in places like Royal Oak, Michigan, and Ridgewood, New Jersey. Edmond became shorthand for what happens when a disgruntled employee explodes under pressure, and the Postal Service was forced to invest in employee assistance programs, threat-assessment protocols, and workplace violence prevention training.
Patrick Sherrill is a foundational case of “workplace mass shooter” incidents; a mid-1980s blueprint that prefigures later office, plant, and government-facility massacres. He was not a serial killer in the classic sense, nor a school shooter, nor a terrorist in pursuit of a broader cause. He was a man whose world had narrowed to a single building and a list of grudges, who turned that cramped universe into a killing field when he decided the only way to resolve his grievances was to annihilate the people he blamed and then himself.
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