Alaska Governor Sarah Palin is guilty of abuse of power, according to a probe by the state legislature.
The Republican vice-presidential candidate was accused of sacking a senior state official, Walter Monegan, in connection with a family feud.
The report could have a significant effect on Republican hopes of winning next month's US presidential election.
She stood accused of dismissing Mr Monegan for refusing to sack a state trooper who was in a bitter custody battle with her sister.
The report concluded a family grudge was not the sole reason for the dismissal, but was a likely contributing factor.
The panel found Mrs Palin in violation of a state ethics law prohibiting public officials from using their office for personal gain.
Several Republican politicians had earlier attempted to have the investigation stopped on the grounds that it was politically motivated.