A couple of days ago, Richard Primus made the case for older, more experienced justices on the high court and laid out an ambitious plan for realizing that goal.

Fair enough, but I feel it's only reasonable to make a more targeted plea for, let us say, the "most experienced" of the current justices to start planning his exit strategy. At an impressive 89 years old, Justice John Paul Stevens really should start thinking about dipping into that retirement fund. Not this year, maybe. Obama will have enough excitement getting Justice Souter's replacement squared away. But Stevens should at least be talking with the White House about when might be a good time for him to go.

Yeah, I know: In this day and age, 60 is the new 30, and 90 is the new 60. And, especially in Washington, people tend to cling to power far longer than is biologically advisable. (The late Strom Thurmond, famously dotty and disoriented in his dotage, is cited most often, but plenty of slightly-less-seasoned players remain who are widely recognized to be passed their cognitive prime but show no signs of ceding the field.) No part of the human body is built to last forever, and even the most hard-charging go-getters start to slow a bit in their 80s and 90s.

Now, save your outrage: This is not to suggest that Stevens himself is declining in his capabilities. Indeed, I sleep easier on the assumption that all of our top jurists remain as sharp as whips. But with a Democratic president in power (and still wielding impressive political capital), now would seem an obvious time for a savvy left-leaning justice to be weighing the pros and cons of staying on the job. It's certainly possible Stevens will remain in top fighting form for another four or eight years. But those aren't the kind of odds most people would bet the future of the court on.

Age and experience are valuable assets. But as with most things, you eventually reach a point of diminishing returns. Here's hoping that Stevens, like Souter (retiring at 69!) and Sandra Day O'Connor (at 75), has the wisdom to bow out before reaching that point. 

--Michelle Cottle