In an interview that aired earlier this week, 60 Minutes’ Lesley Stahl asked President-elect Donald Trump if he would take the office’s $400,000 salary. “Well, I’ve never commented on this, but the answer is no,” Trump said, repeating precisely the position he’d articulated during the campaign. “I think I have to by law take $1, so I’ll take $1 a year.”

In his first inaugural address, George Washington declared that he was not terribly interested in “any share in the personal emoluments” of the presidency. But though delivering inaugural addresses is not required by the Constitution, getting paid to be president apparently is. Congress refused his offer, voting him a $25,000 salary; Washington accepted it.

“The constitutional intent is to assure the financial independence of the President so that he would not be impoverished and not be susceptible to corruption which might jeopardize the public interest,” one former representative offered at a 1999 congressional hearing on the presidential salary. In other words, an American should be able to be able to serve in the White House without going to the poorhouse--or being tempted to pursue his own financial interests at the expense of the public good. And so, despite the fact that George Washington was financially comfortable and the United States was not, the precedent was set.

In spite of his history-defying tendencies, when Trump is sworn-in next January and delivers his inaugural address, he will not be the first American president to decline a salary. That honor belongs to Herbert Hoover, the 31st president, a fellow Republican, and one of the wealthiest men to ever assume the office. “Hoover didn’t need the money,” Professor Glen Jeansonne, whose biography of Hoover came out last month, said. “He spent the first half of his life making money and the second half giving it away.”

Aside from wealth and party, Hoover and Trump don’t share much else in common. As Jeansonne noted, Hoover was an exceedingly modest Quaker from West Branch, Iowa, an orphan who ultimately married just once, who was popular among black voters, and who rejected a government paycheck throughout decades of public service. “Hoover’s refusal to accept salary wasn’t limited to the presidency, it included every other public position he ever held or humanitarian position,” Jeansonne explained, listing Hoover’s posts as a food administrator during the First World War as well as the head of two Hoover Commissions in his post-presidency. “He even paid his own expenses.”

John F. Kennedy followed suit, forswearing roughly $500,000 in cumulative pay during his nearly 17 years as a congressman, senator, and president. “Kennedy certainly didn’t need the money and I think that’s the reason he did it,” said Jeansonne. “He could live very well for the rest of his life on the money he inherited.” Like Hoover, Kennedy would annually disperse his salary to a handful of different charities.

But the constitutionally-mandated presidential salary may do more than allow middle-class Americans to serve as president or suppress the temptations of corruption. It also signals that the presidency is not just a symbolic post, but a job, with a salary that must be earned. Refusing it, as Washington learned, can be interpreted as a sign that a president holds himself above the ordinary rules.

So will it work for Trump? Last week, around the time that Trump sat down with Lesley Stahl, NBC observed that the president-elect had devoted about a quarter of his biography on his presidential transition website to listing his various luxury properties around the world. Following the interview, Ivanka Trump came under scrutiny after her company sought to hawk the $10,000 bangle she wore on the air. His willingness to forgo a salary seems unlikely to quiet critics concerned that he intends to use the presidency to profit himself and his family.