The Colorado Supreme Court suspended Mesa County Court Judge Michael J. Grattan on Thursday amid a misconduct investigation.

The court’s Sept. 10 order gave Grattan 21 days to explain why his paid suspension should not continue through the end of his disciplinary proceedings. Chief Justice Monica M. Márquez did not participate in the order and did not provide an explanation for her recusal.

Because of the confidentiality provisions built into the disciplinary process, the details surrounding the misconduct investigation are not yet public. Anne Mangiardi, the director of the Colorado Commission on Judicial Discipline, said she could not disclose her office’s Supreme Court filing that requested Grattan’s suspension.

Daniel P. Rubinstein, the Mesa County district attorney, said he knew nothing further about Grattan’s circumstances but that his office would have to adjust to any shifts in Grattan’s caseload to other judges during the suspension.

Colorado Politics invited Grattan to comment through the Mesa County court clerk and executive but did not receive an immediate response.

Grattan was in private practice in Grand Junction through 2016, when then-Gov. John Hickenlooper appointed him to the county court bench. He received favorable recommendations from the citizen-led performance commission during his 2020 and 2024 retention elections.

“Judge Grattan pays attention to and shows concern for the people appearing in his courtroom, regardless of their status,” performance commissioners wrote in 2024. “In criminal cases, he has a stated goal of helping ensure that the defendant reforms and gets out of the criminal justice system. He is well organized and prepares in advance for his docket. By studying and reading he strives to keep informed and up to date on the law.”

The commission also called Grattan a “dedicated, responsible, and conscientious judge.”

If the discipline commission initiates formal proceedings against Grattan, a three-member panel consisting of a judge, a lawyer and a non-attorney will adjudicate the misconduct allegations.