Defensive Team Requirements
ARTICLE 5. The defensive team requirements are as follows:
a. Each of the following (1.-5.) is a dead-ball foul. Officials should blow the whistle and not allow the play to continue. After the ball is ready for play and before the ball is snapped:
4. Player(s) aligned in a stationary position one yard from the line of scrimmage may not make quick, abrupt or exaggerated actions that are not part of normal defensive player movement.
5. No player shall use words or signals that disconcert opponents when they are preparing to put the ball in play. No player may call defensive signals that simulate the sound or cadence of, or otherwise interfere with, offensive starting signals.
