A fixed term for Supreme Court justices?

Ronald Brownstein, one of my favourite political reporters, has a good piece in today's L.A. Times on the lifetime tenure of Supreme Court justices:

Justices today, on average, remain on the high court longer and retire at a more advanced age than ever before. Supreme Court justices now routinely serve a quarter-century or more...

The Soviet Politburo probably turned over faster.

Which is why an informal band of prominent legal thinkers from left and right is challenging the Constitution's grant of lifetime tenure to Supreme Court justices. With life spans lengthening, and the court's members clinging so tenaciously to their robes, these critics want to limit justices to a single fixed term, usually set at 18 years.

So far, no prominent politician has joined them. But the idea seems destined to generate more discussion as frustration in both parties mounts over the process of selecting and confirming Supreme Court nominees.

There are persuasive arguments both for and against the status quo (i.e., lifetime tenure), but the intense politicization of the nomination process and the fact that justices may sit on the Supreme Court for decades (Roberts could be there for 30 years or more) suggest to me that a fixed term might not be such a bad idea.

(At Political Animal, Kevin Drum would seem to agree.)