Cheating will not be tolerated. The Head Judge reviews all cheating allegations, and if they believe that a player has cheated, they will issue the appropriate penalty based on the Infraction Procedure Guide or Judging at Regular Rules Enforcement Level document. All disqualifications are subject to DCI review and further penalties may be assessed.
In short, cheating occurs when a person breaks a rule, is aware that they are doing so, and is attempting to gain advantage from their action. For a more detailed discussion about cheating and how to handle this infraction, see IPG 4.8. The penalty for this infraction is Disqualification, and the Head Judge must follow the Disqualification Process.