You observe movement in either line just as the ball is snapped. You know it is a foul, but do you prevent the play from proceeding (dead-ball foul) or do you allow the play to continue (live-ball foul)?

Discerning between those two types of fouls is an absolute must for officials. Here is an example of something you do not want to happen.

Play 1: Before the snap, the right guard A1 abruptly comes out of a three-point stance. The linesman throws a flag but does not stop the play. B2 intercepts a pass and runs for a touchdown. The linesman reports illegal motion to the referee. Ruling 1: That movement is a false start, not illegal motion. Because false start is a dead-ball foul, the play never should have happened. Thus, the score is negated.

How would you like to be the linesman that has to tell the head coach that the proper foul is going to be enforced and your huge error cost him six points?
That situation exemplifies the importance of knowing what are live-ball and dead-ball fouls before, or fouls simultaneous with the snap (we’re not dealing with free kicks here).
Prevent the play from starting for dead-ball fouls. Your protocol for pre-snap infractions should be:

  • Blow your whistle.
  • Throw your flag high into the air.
  • Give the stop-the-clock signal. (It’s a good habit to give that signal even if the clock isn’t running.)

Then there are the fouls that occur concurrently with the snap. That is, there is no foul until there is a legal snap. You might observe a potential illegal act, but it cannot be flagged until the ball is snapped because something might happen to prevent the snap or it could be corrected before the snap. The protocol for such fouls is:

  • Throw flag high into the air.
  • Do not stop the play nor blow your whistle.
  • Do not stop the clock.
  • Cover the play to normal completion. When the down ends, give the stop-the-clock signal and report the live-ball foul to the referee.

Illegal shift and illegal motion are among the live-ball fouls that occur at the snap (NFHS 7-2-7; NCAA 7-1-4b).

In NFHS, a shift is the action of one or more offensive players who, after a huddle or after taking positions, move to new set positions before the ensuing snap (2-39). NCAA defines a shift as a simultaneous change of position or stance by two or more offensive players after the ball is ready for play before the snap for a scrimmage down (2-22). NCAA adds that it is a dead-ball foul when all team A players never become set for a full second before the snap (7-1-2b-5).

Play 2: When the ball is snapped, (a) two backs are in motion, (b) a motion back is moving forward toward the line or, (c) A1, on the line, shifts to the backfield and is motionless for two seconds. He then runs parallel to the line. Ruling 2: In both codes, it is a foul for illegal shift in (a) and illegal motion in (b). If the penalty is accepted, team A is penalized five yards from the previous spot. The act in (c) is legal.

Play 3: A1 and A2 are in motion at the same time. Before a snap, (a) team A calls timeout, (b) time in the quarter expires. Ruling 3: In both codes, there is no foul in (a) or (b), as there was no snap.

Play 4: All team A players are motionless for three seconds. Before the snap, two of them change their positions and both are moving when the ball is snapped. Ruling 4: Live-ball foul for illegal motion. All team A players must come to a complete stop for at least one second before the snap. The five-yard penalty is enforced from the previous spot.

Play 5: Team A breaks the huddle after the ready signal. Ten players settle into their positions and stop, but A1 never pauses and is still moving when the ball is snapped. Ruling 5: Live-ball foul for illegal shift in NFHS (7-2-6 Pen.). Dead-ball foul for false start in NCAA (7-1-2b5).

Illegal formation is another live-ball five-yard penalty from the previous spot (NFHS 7-2-5; NCAA 7-1-4a-4).

Play 6: Team A’s ball, third and 10 at its own 20 yardline. Before the snap, team A has six players on the line and five players in the backfield. A1 receives the snap and throws a pass that gains 20 yards. Ruling 6: Live-ball foul for illegal formation. Team B will accept the penalty making it third and 15 at team A’s 15 yardline.

A player who enters the neutral zone may or may not foul, depending on the code and the status of the ball. In NFHS, encroachment is a dead-ball foul that occurs when a player is illegally in the neutral zone during the time interval starting when the ball is marked ready for play and until the ball is snapped (2-8).

NCAA has an offside foul that is a live-ball foul on the defense (7-1-5b-1).

Play 7: B1 moves into the neutral zone without contacting any team A player. No offensive player reacts. The ball is snapped while B1 is still in the neutral zone. Ruling 7:

In NFHS, that is encroachment as soon as B1 enters the neutral zone. The ball remains dead and team B is penalized five yards. In NCAA, play does not stop. That is a live-ball foul for offside. Team B is penalized five yards from the previous spot.

Had there been contact, team B would have been guilty of a dead-ball foul for offside (7-1-5a-2). If a team B player enters the neutral zone and that act causes a team A lineman lined up head-on with the offending team B player or on either side of him to immediately react by moving, the team A player is not guilty of a false start and team B is penalized for offside (as seen in the PlayPic on pg. 14). A team B player may threaten a maximum of three team A linemen (7-1-2b-3 Exc., AR 7-1-3 V Note).

Play 8: While the quarterback is calling signals, (a) guard A1, or (b) defensive tackle B2 is lined up in the neutral zone. Ruling 8: As seen in the PlayPic above, in NFHS, in (a) and (b), the officials prevent the snap and assess five-yard encroachment penalties against the guilty teams. In NCAA, the ruling is the same as in NFHS. In (b), play continues. After the play, team B will be charged with a five-yard live-ball penalty for offside enforced from the previous spot.