Suppose Person A is accused of an act, which in this case is a hate crime. Person A then points to the actions of Person B, who has committed similar but a more severe form of that action.
This is used by Person A to lessen the severity of their action by referring to Person B.
Ex. Person A has referred to an African American using a derogatory, racist term. When accused as a racist, person A states "Well, Person B has been using this all the time and no one says anything to him/her!"