We’ve talked all about the misguided reasons downward elbows are illegal, but never why knees to the head on the ground are. It’s a fairly well known story, but Josh Gross has just dug the story up again and I figure it’s worth sharing for those who don’t know and for those who just know that ‘it’s Gan McGee’s fault’:

Watching Larry Hazzard Sr. through the chain-link fence, it was clear his discomfort intensified with each successful blow.

Inside the cage on Sept. 20, 2000, Gan McGee had just finished blasting an overmatched Canadian kickboxer when the referee assigned to work mixed martial arts’ first regulated event in a major state stopped the bout. Seated cage-side inside the Tropicana Hotel and Casino on Atlantic City’s rundown boardwalk, the now former New Jersey State Athletic Control Board chief turned and whispered to one of his deputies. He wasn’t concerned that Brad Gabriel’s evening ended with knees to the head. Rather, Hazzard wanted to discuss where McGee scored his technical knockout.

Knees to the head of a grounded fighter — a position in which anything more than the soles of a fighter’s feet touched the canvas — had, until that night, been an accepted attack in MMA. Of course, virtually anything was legal in the earliest incarnation of the sport, but under the rules outlined by the New Jersey board, grounded knees to the cranium were as legal as a punch or a rear-naked choke. That is, until Hazzard saw them in action. (It didn’t help that McGee, a 6-foot-10 training partner of Chuck Liddell, delivered the strikes on an opponent possessing limited grappling credentials.)

After Hazzard instituted what would later become known as the “Gan McGee Rule,” knees aimed at a downed fighter’s head were effectively outlawed in North America. Eight years later, however, the debate over which techniques should be allowed in mixed martial arts competition, including McGee’s knees, remains unsettled.

The above picture from Full Contact Fighter seems to be the only record of the knees.