Sen. Cory Booker (D-NJ) has had trouble separating himself from pack in the crowded Democratic presidential field, but on one count at least he’s stood out: He has by far donated the largest percentage of his income among the candidates.

Business Insider reported on Thursday that Booker donated $24,000 of his $152,639 income in 2018 to charity. And over the past 10 years, CNN reports that Booker has given about $460,000 to charity. That’s a serious, long-standing commitment to giving back — and it’s enough money to have potentially done a ton of good.

Until Cory Booker released his tax returns on Wednesday, revealing that he donated 15 percent of his 2018 income to charity, none of the candidates were looking so great. As my colleague Dylan Matthews reported in the April 20 Future Perfect newsletter:

The most generous of the bunch was Elizabeth Warren, who donated 5.5 percent of her and her husband’s earnings. Jay Inslee gave 4.1 percent; Bernie Sanders, 3.4 percent; Amy Klobuchar, 1.9 percent; Kirsten Gillibrand 1.7 percent; Kamala Harris, 1.4 percent; and Beto O’Rourke a whopping 0.31 percent. O’Rourke later told reporters that public service is his way of giving back.

Those numbers are pretty unimpressive — many of those candidates are lagging the average American in the percentage of income they donate to charity (about 3 percent), despite all having annual incomes above $200,000.

Booker’s giving is certainly notable and worthy of some praise. Like my colleague Dylan Matthews and many other effective altruists, I’ve signed the Giving What We Can pledge to give at least 10 percent of my income to highly effective charities, and certainly my first reaction when I heard Booker’s numbers was delight that someone in the running for the presidency cares about this like I do.

Donating a large chunk of your income is unusual in American society. A community that encourages donating significant money, helps people budget and plan for it, and applauds people when they reach it makes a big difference for individuals who are trying to hold ourselves to a higher standard. And when you’re part of a subculture like effective altruism, it’s rare to see any of your values reflected in mainstream politics. Booker, like us, clearly has a sincere commitment to giving.

But doing good in the world is more complicated than giving a lot of money. Conversations about giving can’t stop at checking what percentage of income you’re donating — and conversations about how politicians can do good in the world shouldn’t really be centered on their giving.

It’s not how much but where you give

I have mixed feelings about evaluating the 2020 presidential candidates by how much they’ve given to charity.

First, a big thing is still missing from our understanding of Booker’s or anyone else’s giving — where they gave. Donating money is commendable because it does good, and ideally it’d be commended only if it does good. And not every charity does. Even well-intentioned programs fail frequently, or work fine at a small scale but not as well at a larger scale. The Giving What We Can pledge isn’t just to donate to charity, but to find the most effective charities out there and give to those.

Charity evaluator GiveWell estimates that you can do an amount of good equivalent to saving a life by donating about $2,100 to GiveWell’s top intervention, seasonal malaria chemoprevention.

On the other hand, lots of charitable interventions do very little good — or might even do harm. Last year, the data came out from a $575 million multi-year project to improve schools, spearheaded by more than $200 million from the Gates Foundation — and the expensive intervention didn’t improve student outcomes at all. Mark Zuckerberg spent $100 million to improve Newark schools (with Booker’s support) and saw some modest gains — accompanied by outrage and local backlash. (Dylan Matthews has pleaded for philanthropists to stay out of education, where their track records are particularly disappointing.)

GiveWell found that these failures aren’t the exception but the norm. “We think that charities can easily fail to have impact, even when they’re doing exactly what they say they are,” they write. “[M]any of the problems charities aim to address are extremely difficult problems that foundations, governments and experts have struggled with for decades.”

Another hesitation I have about the focus on politicians’ giving is that the decisions they make as senators, Congress members, and governors are of far greater altruistic significance than where they donate. Booker’s 2018 donations, if he had given to the most cost-effective, high-impact charities, could at most have saved several lives; as a senator, he affects hundreds of millions of them.

It makes sense that combing through tax returns is so popular. It gives you a look 10 years back into a candidate’s history, before they were polished presidential candidates who carefully manage their image. But fundamentally, just as it matters whether charitable donations actually do any good, the thing that matters about presidential candidates is whether they’ll actually do any good. Booker’s proposed policies are the thing to evaluate him by. While his generosity definitely might mean that we like him as a person, it shouldn’t be the thing that decides our vote.

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