have a case

have a case (against someone)

to have much evidence that can be used against someone in court. Do the police have a case against John? No, they don't have a case.
See also: case, have
References in classic literature ?
I only desire to satisfy you that we have a case worth trying.
TWO detectives have a case to answer for misconduct in the case of Lostprophets singer Ian Watkins, a watchdog has said.
But the inquiry recommended two detectives have a case to answer for misconduct for not complying with force policy on recording decision-making and not pursuing all reasonable lines of inquiry.