TAMPERED

To make unauthorized or improper alterations, sometimes causing deliberate damage; to meddle (with something).

"The alarm had been tampered with and didn’t go off when it should have."

To try to influence someone, usually in an illegal or devious way; to try to deal (with someone).

"Prosecutors argued that he would tamper with witnesses if bail was granted."

To meddle (with something) in order to corrupt or pervert it.