Cebull himself and 10 others requested the misconduct investigation after The Great Falls Tribune reported the judge forwarded an email in February 2012 that included a joke about bestiality and Obama's mother. Cebull apologized to Obama after the contents of that email were published.
The investigation looked at four years of Cebull's personal correspondence sent from his official email account.
Cebull told the 9th Circuit panel that his "public shaming has been a life-altering experience." Nominated by former President George W. Bush, he received his commission in 2001 and served as chief judge of the District of Montana from 2008 until 2013.
Named as defendants in the case were the office of 9th Circuit Executive Cathy Catterson and the Committee on Judicial Conduct of the Judicial Conference of the United States.
Ninth Circuit spokesman David Madden said he could not comment on the pending petition.
The plaintiffs attempted in May to directly petition the 9th Circuit. That was rejected by the court's clerk, who said the petition needed to be filed first at the district court level.