PHOENIX (AP) — An Arizona ethics board disbarred Maricopa County’s former top prosecutor on Tuesday for violating the rules of conduct for lawyers in bringing criminal charges against two county officials and a judge in December 2009 with the purpose of embarrassing them.

All three investigations were dismissed after a judge ruled that Andrew Thomas, the former county attorney, had prosecuted one of the officials for political gain and had a conflict of interest. Other county officials and judges who were at odds with Mr. Thomas and his top ally, Sheriff Joe Arpaio, were also investigated by the two but were not charged.

The three-member disciplinary panel of the Arizona courts ruled that Mr. Thomas and an assistant prosecutor broke criminal intimidation and perjury laws in knowingly bringing false bribery charges against Judge Gary Donahoe, then of Superior Court. The panel ruled that the evidence suggested that Sheriff Arpaio and one of his aides conspired with the two prosecutors.

The decision was the first official comment by the state’s legal establishment on the validity of the investigations and supported lawyers who said Mr. Thomas and Sheriff Arpaio wrongly went after judges, lawyers and government officials who crossed them.