hello there,
my son is on parole and was arrested for dui. his parole officer decided to violate him though he initially decided against it. next day he arrests my son anyway. my son had been out for some months and was working, giving clean tests, obeying all conditions of his parole, so i feel the agent had no right to ''change his mind''. does he have the right to do that?

The agent has every right to change his mind. The purpose of parole is to "allow the parolee to serve his sentence outside the prison walls." your son was obeying all the conditions of parole, but he failed to obey directive #1 - "obey all laws."