Divorce courts require proof be given that the grounds actually exist. This can be accomplished by providing testimony from a hired detective with documentation of the spouse's bad behavior or from someone who witnessed or has first-hand knowledge of the spouse's bad behavior. There are defenses a spouse can use to convince the court that he or she is not at fault in order to have the grounds dismissed and possibly prevent a fault divorce. These defenses include collusion, condonation, connivance, and provocation.