After a substitute enters the field of play and trips an opponent from behind (blind side) the referee stopped play and showed the substitute the red card. He restarted with a IFK. At the end of the game while writing the report the referee is struggling with what reason to write for the red card for.

The LOTG states: A player, substitute or substituted player is sent off if he commits any of the following seven offenses:
• serious foul play
• violent conduct

The referee wants to go with SFP since the play wasn’t that violent to go with VC. But AR reminds him that ATR 12.33 says:
This does not include serious misconduct by substitutes, who should be punished for violent conduct if they commit an act as described in the first paragraph of this section. (See 12.34.)

My question, can the ATR trump what is very clearly stated in the LOTG?

Answer (February 10, 2012):
There is nothing in the Advice to Referees that recommends anything that is contrary to or “trumps” the Laws of the Game. The Laws of the Game always take precedence over anything in the Advice, as clearly stated in the introduction to the Advice. Your scenario is clear-cut and the same answers are in both publications.

First you must justify the nature of any misconduct committed by the substitute before you decide how to punish it. In your scenario the sub who enters the field and trips an opponent, but has not committed any act of a violent nature. Why would you send him off for serious foul play? A substitute cannot commit serious foul play. He can commit violent conduct, but your scenario does not include any act of violence. Therefore the information in Advice 12.33 is absolutely correct: The substitute MUST be cautioned for unsporting behavior (entering without permission), but not necessarily until he interferes with play, and the opponents awarded an indirect free kick from the place where the ball was when play was stopped. If the referee “needs” the second sanction for game management purposes, then he or she should caution the substitute for a second instance of unsporting behavior, tripping the opponent. If the trip from behind involved excessive force, then send the sub off for violent conduct.