An illegal practice in football in which a player contacts another player by leading with the crown of his helmet.
The practice of leading with the head by either an offensive or defensive player outside of the tackle box incurs a 15-yard penalty and depending on the circumstances, can also result in a fine against the offending player. If both a defensive and offensive player are called for leading with the head on the same play, the penalties offset. The “crown” of the helmet constitutes the topmost portion of the helmet. The NFL’s reasoning for the rule (introduced in 2014) is to promote health and safety in the league. Banning this practice is intended to prevent intentional tackles that lead with the head or the lowering of the head by a running back against defenders because the helmet itself can cause injury (both to the recipient of the collision and the player initiating the collision). Enforcement of the penalty is usually contingent on whether the action appeared to be intentional or not—incidental collisions or an attempt to lead or protect with the shoulder will often not incur a penalty.