kneecap

[Mullins, Bill]

OED has "kneecap" (verb -- to injure, usually shoot, the knees to make a political or other motivational point) in Aug 1975.

The  [London] Times, Nov 20, 1974; pg. 16; col E 
     Is this the civil war everyone feared in Ulster? Christopher Walker.

"An indication of the brutality which can be used in the name of internal discipline was provided recently when a man from the Shankill Road was "kneecapped" with a Black & Decker electric drill."