character assassination
A deliberate attempt to destroy the reputation of a public figure by releasing, revealing, or creating defamatory or damaging information about them. The so-called expose on the senator is character assassination, pure and simple. Releasing those decades-old photos this late in the campaign amounts to character assassination—and it will probably work.
character assassination
Fig. seriously harming someone's reputation. The review was more than a negative appraisal of his performance. It was total character assassination.