SAN FRANCISCO (CBS/AP) -- Now 84, federal appellate court Judge William Canby made the difficult decision a few years ago to mostly stop hearing cases after a 30-year career. He was sharp and healthy, but didn't want to risk mental decline that would lead him to make mistakes, he said.
"It seemed to me if the goal is to work until you are no longer able, you will work a couple of years too long," he said.
Canby's decision reflects one of the unique job hazards federal judges face: age-related mental decline. Unlike judges in most states, U.S. Supreme Court justices and federal appellate and district court judges are appointed for life. To be removed, they must be impeached by Congress, which has occurred only a few times.
Some judges stick around too long, colleagues and court observers say, prompting complaints that they are showing signs of senility such as forgetfulness, an inability to follow arguments and long delays in deciding cases. Judges say they often enlist peers or family members to quietly and delicately encourage the person to seek help or leave.
But the 9th U.S. Circuit Court of Appeals, which includes federal courts in California and eight other Western states, has taken a more pro-active approach to the problem of mental decline by trying to get its judges to think about the condition, plan for it and handle it appropriately if it comes up.
The circuit court holds regular seminars led by neurological experts to teach its chief judges about the signs of cognitive impairment. It has set up a hotline where court staff and judges can get advice about dealing with signs of senility in colleagues. It has also encouraged judges to undergo cognitive assessments and designate colleagues, friends or family who can intervene if concerns arise about their mental health.
"We're an organization that is required to police ourselves," said Phyllis Hamilton, chief judge in the Northern District of California and head of the 9th Circuit's wellness committee. "If we wish to retain the goodwill and confidence of the public in our ability to render justice by judges who are unimpaired ..., we have to take steps."
The U.S. Constitution guaranteed federal judges lifetime appointments to maintain judicial independence by preventing the easy removal of judges for unpopular decisions.
But life expectancy when the Constitution was signed in 1787 was under 40. It is now about 79.
Some judges serve well beyond that age. Oliver Wendell Holmes Jr. is the oldest person to serve as a U.S. Supreme Court justice, retiring in 1932 at the age of 90. U.S. District Court Judge Wesley Brown in Kansas was the oldest working federal judge in the country's history when he died at the age of 104 in 2012.
Critics say the risk of cognitive decline is among several factors that favor imposing a retirement age or term limits on federal judges. Most states require appellate judges to retire between 70 to 75 years old, according to the National Center for State Courts. State judges may also face elections and generally can be removed by disciplinary commissions without turning to the state legislature.
"(Federal judges) could be independent and still have a retirement age," said Paul Carrington, a law professor at Duke University. "I can't believe policing themselves is a complete answer to the problem."
With no requirement that federal judges undergo cognitive tests, it's not known how many experience mental decline in their later years. Anecdotes from judges and court observers, however, indicate it may be more than an isolated problem.
Richard Carlton, who runs the 9th Circuit's counseling hotline, said he gets a handful of calls a year from judges concerned that a colleague may be impaired.
"A lot of these situations resolve themselves pretty quickly," he said. "It often times turns out to be some kind of physical condition or some new medication somebody's taken, or they're in the process of transitioning from senior status to full retirement."
Over the past five years, the 10th US. Circuit Court of Appeals, which includes Colorado and five other Western states and has its own judicial health program, has addressed at least two complaints that could reflect mental decline.
One accused a senior district judge of falling asleep during a court proceeding.
The judge said a tiring family emergency may have been to blame and indicated that he would reduce his caseload and decline trials and lengthy hearings, according to a 2010 order by the circuit's chief judge.
The second complaint by a judge's former law clerk accused the judge of forgetfulness and erratic, abusive behavior. The judge underwent psychological screening and was cleared of any mental disability, according to a 2014 order by the circuit's chief judge.
The judges and complainants were not identified.
Canby encourages his colleagues to get ahead of any complaints by, like him, voluntarily declining to regularly hear cases at some point. In an article in the 9th Circuit's wellness newsletter, he said impaired judges threaten public confidence in the judicial branch.
"If a great majority of judges are determined to keep on judging until they are no longer mentally able to perform properly, instances of impaired judges still making decisions will multiply," he wrote. "The consequence of such behavior will be an unacceptably high rate of institutional damage."
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