ON THE third season of “House of Cards”, the Netflix show about Washington Machiavellianism gone haywire, a fictional Supreme Court justice mulls retirement when he is diagnosed with Alzheimer’s. Aside from some overblown criticism of the conservative justices, nobody is speculating that anybody on the real-life Supreme Court is suffering from a degenerative brain disease. But the show’s plotline calls attention to the fact that, barring death or an impeachable offence, the justices themselves decide when to hang up their robes. And today’s Supremes are no spring chickens. Ruth Bader Ginsburg, the liberal lion who has resisted calls to retire during Barack Obama’s presidency, is 82. Antonin Scalia, on the right, and Anthony Kennedy, in the centre, are both 79. Stephen Breyer is 77. Four justices—Clarence Thomas (67), Samuel Alito (66), Sonia Sotomayor (61) and the chief, John Roberts (60)—are sexagenarians. The new kid on the bench, Elena Kagan, is a wee 55. If nobody leaves the court in the next five years—an unlikely permutation—the average age of the justices will be 75 at the end of the next president’s first term.

Is there anything wrong with a grey bench? Fix the Courts, an advocacy group, says yes, and proposes that future nominees to the Supreme Court take a pledge to serve no more than 18 years before stepping down. Given how hard it is to amend the Constitution, this proposal is less quixotic than an attempt to change the provision in Article III permitting justices to “hold their offices during good behaviour”. But are term limits for justices, whether imposed or voluntarily agreed to, a good idea?

Fix the Courts has one primary argument in favour of fresh blood, and it’s not quite convincing. The goal of life tenure was to “shield those serving on the court from the political pressures of the day”, the group observes, but “today’s justices...are polarised along partisan lines in a way that mirrors our other broken and gridlocked political institutions”.

There are three problems with this line of reasoning. First, while the Roberts Court issues more closely divided rulings than previous courts ever did, it’s a myth that “today’s justices” are more political than their forebears. In 1803, under Chief Justice John Marshall, the court flexed its Federalist party muscle against the new president, Thomas Jefferson, in its ingenious Marbury v Madison ruling. During the Lochner era from 1905 to 1937, the court routinely struck down progressive legislation to improve worker health and safety and to extricate the country from the Great Depression. It was enough to spur Franklin Delano Roosevelt to propose an ill-fated court-packing plan to change its composition and the tenor. (He withdrew the plan when the court started upholding New Deal policies.)

Second, there’s no reason to believe term limits would put a damper on the court’s politicisation, or fundamentally change the “political circus” of the Senate confirmation hearings. Even if nominees taking the pledge can be trusted to keep their word—remember, it isn’t legally binding—18 years is still a long time. Political actors will remain quite worried about who ends up among the nine most powerful jurists in the land.

Third, 5-4 decisions show the justices may be “polarised” on certain issues, but it does not mean the justices are “partisan”. Nobody on the court seeks to toe the line of either of the major political parties. In fact, during the term that ended in June, many of the justices—the conservative ones in particular—were willing to stray from their typical ideological camps in plenty of cases. This past spring, for example, Chief Justice Roberts voted with the four liberal justices to save Obamacare and to uphold restrictions on fundraising by judicial candidates. Justice Thomas voted against his conservative brethren in permitting Texas to refuse to print Confederate flags on licence plates. And Justice Alito came to the defence of pregnant women’s rights in the workplace.

Eliminating life terms for justices is questionable as a solution to the purportedly novel problem of judicial politicisation. But there are other good reasons to wish for a court where no one stays on for three or four decades. At the founding, Thomas Jefferson suggested that since the “earth belongs usufruct to the living”, America ought to have a constitutional convention every 20 years to scrap the old document or subject it to revisions. That proposal did not go anywhere and may not have been a recipe for the early republic’s stability. But there is wisdom in the general notion of more frequent leadership change.

No matter how wise or enlightened they may be, a bench of seven or nine octogenarians will have a circumscribed perspective on the country for which they are adjudicating fundamental questions. Encrusted jurisprudence won’t necessarily be bad for the country: as Alexander Hamilton pointed out in Federalist 79, the “danger of a superannuated bench” resulting from aged judges is “imaginary”. Indeed, Justice Ginsburg shows in both her written opinions and incisive questions during oral argument that she is as vigorous intellectually as she has ever been. But breathing new life into the nation’s highest court more often—even if it does not make the tribunal any less political—would bring more dynamism to the judiciary, jog the justices' decision-making patterns and narrow, even if only slightly, the yawning gap between the enrobed ones and everyday citizens.