The Fairest Way to Keep Cognitively Declining People From Being Elected

Plenty of occupations in the United States have justifiable age limits. Commercial-airline pilots cannot be over 65. Mandatory retirement for all federal law-enforcement officers is 57. Two-thirds of S&P 500 corporations have mandatory age limits for board members, mostly 72 or 75. Many consulting and law firms require their partners to retire in their 60s.

The presidency, right now, has no such official restrictions. Age might still disqualify a candidate: After President Joe Biden’s horrendous debate performance earlier this year, his party pressured him to recognize how his more obvious limits, and appearance of cognitive decline, were hurting Democrats’ chances of keeping the Oval Office. Former President Donald Trump, at 78, is still his party’s candidate, despite delivering incoherent speeches that raise legitimate questions about his mental capacities.

Beyond Biden and Trump, other political candidates and elected officials have displayed signs of age-related cognitive decline: Think of Dianne Feinstein and Orrin Hatch. The country has an interest in ensuring that cognitively impaired people are not elected to office—and, in particular, to the presidency, the most powerful job in the world. The simplest and fairest mechanism to protect the United States from this problem is to institute an upper age limit for all federal elected officials and judges.  

Currently, 32 states and the District of Columbia have age limits for judges. Mostly, these are set at age 70, but some are higher: 72, 73, 75. Vermont’s mandatory age limit for judges is 90. South Dakota is voting on a ballot measure this year to amend the state constitution to limit the age of its congressional candidates to 80. There is bipartisan support for such age limits. Nearly 80 percent of the American public endorses an age limit for federal elected officials, and 74 percent for Supreme Court justices. Most respondents to one CBS poll thought the limit should be under 70 years of age for politicians.

Opponents of age limits sometimes argue that these measures usurp the public’s right to choose our leaders—that democracy can self-correct, because voters can decline to endorse aging politicians who are losing mental function. If Biden had stayed on the ballot, no one would have been forced to vote for him.

But incumbent advantage makes elections poor vehicles for rejecting cognitively declining politicians. Biden’s 2024 presidential campaign was a clear example of this: By insisting on running as the incumbent, Biden cleared the field, scaring away other potential candidates. Challenging an incumbent elected official in a primary can be career-ending and is not something politicians undertake voluntarily. Consequently, when Representative Dean Phillips tried to recruit a plausible alternative to run against President Biden, no one accepted, leaving him, a junior member of the House of Representatives, the only candidate to challenge the president. Unsurprisingly, this ended Phillips’s political career. And because Democratic voters had few other choices, they handed Biden primary after primary, even though the majority thought he was too old and becoming too impaired. Only deus ex machina in the form of Nancy Pelosi, Barack Obama, Chuck Schumer, Hakeem Jeffries, big-money donors, and a few others forced the unprecedented: a candidate with sufficient delegates to be nominated the presidential candidate of a major party withdrawing from the race. It took Biden’s exit for a full field of possible successors—including Vice President Kamala Harris—to come into public view.

Another objection to mandatory age limits is that any cutoff would be arbitrary, given that age-related mental decline is not the same for every person. Some people lose fluid intelligence at a young age, whereas some octogenarians are still mentally sharp enough to hold office and be wise judges. And, yes, age limits are arbitrary. So are age minimums, which almost all countries—including ours—have for voting and for holding office. But the alternative is mandatory mental-competency tests. These, too, are arbitrary, vague, and easily manipulated. Some people are great at test-taking, and others (like me and my two brothers) are bad at standardized tests of any kind. Screening tools and assessments for dementia may examine different dimensions of cognitive ability, but they are almost never diagnostic by themselves. Any system of testing would first have to determine the right cognitive test for being a senator, a federal judge, or the president, and developing a validated instrument for these unique positions would require data that do not exist. Second, a testing system would need someone to determine what constitutes passing. Who would that be, and how would they be insulated from special pleading by powerful people? An age limit, conversely, is unambiguous and not open to manipulation.

And choosing one based on when people are more likely to start losing function is possible. Higher age cutoffs, such as the one in Vermont for judges, would be riskier: At age 80, the risk of Alzheimer’s dementia, for instance, is nearly 20 percent, and at 85 is greater than 33 percent. In adults with at least college education—which all judges and almost all elected officials have—the first signs of cognitive impairment appear at an average age of 76. In line with the age limits for boards at many corporations, I would propose 75 as the age cutoff.

Some people argue that such a cutoff would exclude the many older people who are mentally intact from providing valuable leadership to the country. An upper age limit of 75 would have excluded from service people such as Benjamin Franklin, who at age 81 was an active participant in the Constitutional Convention, as well as Oliver Wendell Holmes and John Paul Stevens, who both retired from the Supreme Court at age 90, having continued to make significant contributions. Maybe the most pertinent of all to this debate is Pelosi, who was 82 when she stepped down as speaker of the House and is still as sharp as ever at 84, wielding tremendous political power (and running for reelection this fall).  

But age limits would not preclude these people from serving the country. They could offer counsel and influence in many ways beyond holding an elected political position or judgeship. Today, sitting presidents call former presidents or Cabinet officials for advice. Presidents have often sent retired politicians on important international missions and even to head delicate negotiations. Mandatory age limits for elected officeholders and judges would not prohibit this type of national service and assistance.

Biden’s exit from the presidential race in July is already seen by most as central to his legacy as a public servant. Using his exit as the impetus to bring mandatory age maximums for all federal elected officials and judges would require a constitutional amendment, the campaign for which former Presidents Biden, George W. Bush, and Bill Clinton could all lead. That, more than anything, would cement Biden’s place in history.