(CNN) -- A federal judge who came under criticism for forwarding a racist e-mail aimed at President Barack Obama earlier this spring will be taking partial retirement, according to a U.S. court website.

Montana Chief U.S. District Court Judge Richard Cebull had apologized and offered regrets for the incident, telling the Billings Gazette at the time it was "a hard lesson to learn."

Cebull will take "senior status," next March, according the judiciary's main administrative office, meaning he will vacate his seat but will be available to hear a reduced caseload. Obama will name the judge's replacement.

Civil rights groups had demanded Cebull's immediate resignation after the e-mail was revealed seven months ago.

He is currently the subject of an internal misconduct review by a panel of fellow judges, the Judicial Council of the 9th Circuit Court of Appeals. That review has not been completed.

Cebull did not write the offensive material, but admitted forwarding the message on February 20 to a few friends after it was sent to him by his brother. The Great Falls Tribune was given a copy and reported that the message said:

"Normally I don't send or forward a lot of these, but even by my standards, it was a bit touching. I want all of my friends to feel what I felt when I read this. Hope it touches your heart like it did mine.

"A little boy said to his mother, 'Mommy, how come I'm black and you're white?' His mother replied, 'Don't even go there Barack! From what I can remember about that party, you're lucky you don't bark!'"

Obama is of mixed race.

"To say it's inappropriate and stupid is an extreme understatement," Cebull said according to the Billings newspaper. "There is no doubt it's racist. It wasn't forwarded for that purpose. If anything, it was political."

The Billings-based judge was named to the bench by President George W. Bush in 2001. He has been chief judge since 2008, overseeing two other full-time district judges, three senior or part-time judges and five magistrates. His chambers did not return a call from CNN for comment.

Cebull said in the interview his conduct in court over many years has shown he is not a racist, but he admitted the public got that impression from the e-mail. "And I don't blame them," he added.

The judge also separately told the Great Falls Tribune, "The only reason I can explain it to you is I am not a fan of our president, but this goes beyond not being a fan. I didn't send it as racist, although that's what it is. I sent it out because it's anti-Obama."

Some advocacy organizations said the 68-year-old Cebull should have fully retired, and should have done so months ago.

"Americans expect the courts to be fair, impartial, and open to all," said Michael Keegan of the liberal People for the American Way. "Cebull clearly demonstrated that he does not have the temperament to serve as a federal judge, period."

Standards warranting removal are not clear, beyond a violation of civil or criminal law. Congress would have to initiate impeachment proceedings, but the few judges to face that have usually resigned before those proceedings went far. There is no indication the judge in Montana would be subjected to either option.

Senior status is a common option for federal judges who have earned enough seniority to qualify for a full government salary while working only part time. A judge must be at least 65 and have served for 15 years. Courts with especially crowded dockets rely heavily on senior judges to help pick up the caseload.

According to the Administrative Office of the U.S. Courts, senior judges essentially provide volunteer service to the courts, and typically handle about 15% of the federal courts' workload annually.

Retired Justices Sandra Day O'Connor, David Souter, and John Paul Stevens are all on senior status. But unlike their lower court counterparts, retired justices cannot sit on any Supreme Court cases.