Last week President Obama announced his nomination for Supreme Court justice, naming Merrick Garland, 63, as his choice to replace Justice Antonin Scalia, who died in February at the age of 79. While Republican senators vowed to block President Obama’s nomination, stalling until the next president takes office, whoever becomes the next Association Justice of the United States Supreme Court will likely have a hand in the interpretation of law for longer than his or her forebear. Life extension is changing the very nature of a lifetime appointment.

The Constitution dictates that justices are nominated and appointed by the president with “the Advice and Consent of the Senate” but there are no laws that put a statute on when the justice actually leaves the court — save for cases of treason, bribery, or other major crimes. This is the way it’s always been; the Supreme Court of today is essentially the exact same institution it was when it was established in 1790.

There are only two ways that justices leave the high court — they retire or they die. And this is a problem. Every other group of public officials is constricted by term limits for a reason. Democratic processes are the lifeblood of democracy. When systems stagnate for too long — and that’s longer for the court than for congress — stability comes at the cost of progress. Antonin Scalia served for 30 years. That would have been considered a very long stretch a century ago. A century from now — if the system is maintained — it might be considered very brief indeed. Medical science can’t defeat death, but it can hold it at bay for a while.

President Barack Obama nominates Merrick Garland to the Supreme Court.

Of the 112 justices who have sat on court, 44.5 percent have died in office while 47.3 percent have retired. The longest a justice has ever served was 36 years and 7 months — William Douglas served from 1939 to 1975 — while Justice Oliver Wendell Holmes, Jr. was the oldest justice to retire when he did so at 90. The average age of retirement of a justice before 1971 was 78.7 while before 1971 it was 68.3.

This is largely because people are living a lot longer now than they ever had before — people over 85 are the fastest growing age group in the country and the U.S. Department of Health and Human Services has declared the increase in life expectancy to be “one of society’s greatest achievements.” Improvements in health, hygiene, and nutrition have reconfigured generational populations and made it so that justices dying on the bench has become a less frequent event. Scalia is only the second justice to die while still on court since 1954.

Does this mean we can trust justices to exit in timely manner? Not really. Though the Supreme Court is not a political body, it is a heavily politicized body. Scalia didn’t want to die, but he really, really didn’t want to die while Obama was in office. In a 2010 paper in the journal Demography sociologist Ross Stolzenberg and law professor James Lindgren analyzed data on every justice from 1790 to 2006 and found that justices purposefully delay their retirement for the benefit of the party of the president who appointed them to court. If you’re a Republican justice, you’re going to wait to retire until it’s safe to say the president is going to put another Republican on court. Given polling numbers, it’s likely Scalia would have had to wait another four to eight years to slip off his robe. And if that delay persisted it’s fair to say that Scalia’s beliefs would have been viewed as increasingly outmoded by a considerable portion of the American electorate.

Though there is a reason Americans don’t vote on Supreme Court cases, there is also a potential danger in the extreme longevity of careers subverting the public interest. Even now, this isn’t a major concern. Scalia’s originalism remained relevant — albeit controversial. But what if he lived to 150? 200? Does it make sense to have laws made in one era consistently interpreted by the standards of another?

In a different paper, Lindgreen and fellow Northwestern professor of law Steven Calabresi make it plain that this “death or retire” paradigm is bad for the country. While it may have made sense in the 18th century for justices to not have term dates, for a justice now to have decades on the bench is “essentially a relic of pre-democratic times that blocks the democratic voting power of the American people.”

“We believe the American constitutional rule granting life tenure to Supreme Court Justices is fundamentally flawed, resulting now in Justices remaining on the Court for longer periods and to a later age than ever before in American history,” the scholars wrote in the Harvard Law Review. “Moreover, the combination of less frequent vacancies and longer tenures of office means that when vacancies do arise, there is so much at stake that confirmation battles have become much more intense.”

The professors also write that a problem of “mental decrepitude” has affected some justices’ mental and physical abilities as they creep into old age. While this is contested — law associate Ryan Park wrote in the Atlantic that as Scalia aged there was no sign that he “had dulled in his ability to navigate the incredible intellectual challenges that were his job description” — there’s no denying that as we get older our brains become more feeble.

As someone’s age increases, their cognitive processing speed slows down, causing them to rely on heuristics (mental shortcuts) more. Studies have found that a reliance on heuristics directly affects decision-making competence while other research has demonstrated that as brains age, frontal lobes deteriorate, causing people to become less capable of controlling their behavior and prejudiced thinking. This is not an ideal scenario for someone disposed with the responsibility of deciding cases that will have a tangible effect on the American people.

The question is whether or not our ability to keep people alive outstrips our ability to keep them mentally agile. Parsing that is incredibly difficult, but let’s put it this way: We know a lot less about neuroscience than we do about cardiac medicine.

So Lindgreen and Calabresi propose a solution: A constitutional amendment declaring that terms be staggered for the nine justices so that every two years there will be one vacant spot. Every one-term president would get to appoint two justices while every two-term president would appoint four. Imposing term limits on justices, they feel, would create democratic accountability. It also reflects a heightened version of how Thomas Jefferson wanted this whole thing to go — in his time he argued that federal judges should have renewable terms of four or six years.

The system of the Supreme Court isn’t likely to change anytime soon, but it is worth questioning why the country is unwilling to change a system that no longer reflects the reality of the times. The longevity of the average Supreme Court justice means that they’ll either die in office, sending the political parties into a scramble, or wait so long to retire that the American people are denied of a democratic principle — a choice in who makes the decisions that will benefit the country. While the president and Congress have control over who sits on the court, the court has the power to amend the Constitution, which dictates the power given to the president and Congress.

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