Section 8 (military) Wikipedia
Section 8 is a category of discharge from the United States military, used for a service member judged mentally unfit for service. It also came to mean any service member given such a discharge or behaving as if deserving such a discharge, as in the expression, "he's a Section 8". The term comes from Section VIII of the World War II-era United States Army Regulation 615-360, which provided for the discharge of those deemed unfit for military service.
Discharge under Section 8 is no longer practiced, as medical discharges for psychological/psychiatric reasons are now covered by a number of regulations. In the Army, such discharges are handled under the provisions of AR 635-200, Active Duty Enlisted Administrative Separations. Chapter 5, paragraph 13 governs the separation of personnel medically diagnosed with a personality disorder.
Section 8 became a household phrase when used in the 1970s TV series M*A*S*H, in which the character Corporal Klinger was continually seeking one (until he eventually abandoned his efforts). Other pop culture references to the term include:The 1987 movie Full Metal Jacket, in which a recruit (Leonard Lawrence, a.k.a. "Private Gomer Pyle") becomes noticeably unstable as a result of the abuse from his drill instructor and platoon-mates. Later in the film, it is mentioned again when Private "Cowboy" mentions how one of his recently deceased platoon-mates was about to be shipped out on a Section 8 for chronic masturbation.
The 2003 movie Basic, in which a DEA agent Tom Hardy (played by John Travolta) investigates a group of rogue Rangers turned drug dealers calling themselves Section 8. They are later revealed to be a black-ops anti-drug unit led by Hardy (now addressed as "Colonel"); the "Section-8" insane-mercenary story is a cover to spook the cartels.
The 2007 video game BioShock, in which Atlas, via radio, informs the player that Fort Frolic has been handed over to a deranged artist named Sander Cohen. "Cohen's an artist, says some. He's a Section 8, says I. I seen all kinds of cutthroats, freaks, and headcases, but Cohen's a real lunatic."
The 2016 movie Hacksaw Ridge, in which Army recruit Desmond Doss is required to undergo psychiatric evaluation or else face a Section 8 discharge for refusing to participate in weapons training because of his religious convictions.