Personally I'd pick 70 as the maximum age for president.
For the House and Senate it doesn't bother me as much because both can continue to function even if several members can't. Having said that, I'd prefer a limit of 70 for those institutions as well.
Both would probably require amendments to the Constitution:
>>>Maximum age limits are considered unconstitutional. Part of the reason that's true dates back to 1995. At the time, Arkansas attempted to deny ballot access to prospective U.S. representatives who had already served three terms and prospective U.S. senators who had already served two terms.
That case was argued in front of the Supreme Court in
U.S. Term Limits, Inc. v. Thornton. The court ruled that the Framers could have created term limits for lawmakers in Congress but chose not to, suggesting that they did not intend for term limits to be part of the Constitution.
The same could be argued against maximum age limits, according to Jeremy Paul, who teaches at Northeastern University School of Law.
"Whether you're talking about adding term limits or whether you're talking about a maximum age, you're still changing the qualifications that are set out in the Constitution," Paul said.<<<
Cognitive testing seems like a more logical way to address the issue, but it would probably lead to endless arguments about the criteria, litigation about whether or not the test was administered properly, etc.
A bright-line age limit would undoubtedly keep some capable people out. On the other hand, there would still be plenty of capable people who could serve and meet an age limit requirement.
With regards to judges, I have mixed feelings about it. There has been a controversy concerning judge Newman, who is 96 years old.
Guest Post by Paul R. Gugliuzza, Professor of Law, Temple University Beasley School of Law The judicial disability proceedings instituted …
patentlyo.com
It's unclear exactly what is driving the effort to remove judge Newman. Most of it seems to be closed-door. According to public reports, it is based at least in part on statements by staff that Newman is losing it.
Newman writes a lot of dissenting opinions, and these seem to be well-written. This creates the appearance that the other judges want to push her out because they are tired of getting skewered by Newman in her dissents.