ARTICLE 9. PLAYERS IN A DEFENSELESS POSTURE. It is a foul if a player initiates unnecessary contact against a player
who is in a defenseless posture. A player who initiates contact against a defenseless opponent is responsible for avoiding an
illegal act. A standard of strict liability applies for any contact against an opponent, even if his body position is in motion, and
irrespective of any acts by him, such as ducking his head or curling up his body in anticipation of contact.
(a) Players in a defenseless posture are:
(1) A player in the act of or just after throwing a pass (passing posture).
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(b) Prohibited contact against a player who is in a defenseless posture is listed below. However, these provisions do not prohibit
incidental contact by the mask or helmet in the course of a conventional tackle or block on an opponent:
(1) forcibly hitting the defenseless player’s head or neck area with the helmet, facemask, forearm, or shoulder, even if the
initial contact is lower than the player’s neck, and regardless of whether the defensive player also uses his arms to tackle
the defenseless player by encircling or grasping him;
I mean, pretty textbook. Penalty all day.