This is because higher earners are in higher tax brackets, which means that giving them a pass on those taxes costs the country more. It is also because wealthy individuals often have appreciated stock that they can donate, which lets them avoid paying the capital gains taxes that they would otherwise owe if they cashed in on that stock themselves.

Finally, you have to itemize deductions to get almost any reduction in taxes from giving. Nearly all wealthy people do so, but it’s rare among lower-income people. The new tax law will make it even rarer; the Tax Policy Center predicts that it will reduce the number of households that take the charitable deduction to 16 million from 37 million.

Eliminating the tax deduction for charitable giving would not be politically viable. But we could limit it, either through lowering the cap on how much of a gift can be deducted or setting a flat percent of each donated dollar that can be used as a credit against one’s tax bill.

We could also call on the philanthropists who are making these enormous contributions to voluntarily forgo the deduction. Many megawealthy individuals have followed Bill Gates’s and Warren Buffett’s lead and pledged to give away half of their accumulated wealth. Perhaps they could also pledge that through their funding of the causes they hold dear, they will neither reduce the ability of our government to fund its priorities, nor shift some of the cost of their gifts onto other taxpayers.

Any of these steps could reduce the amount of charitable giving. But some studies suggest that donations would fall far less than tax receipts would increase. One frequently cited figure is that for every additional dollar raised by the government through changes in the deduction, charitable giving might fall by 40 cents. This is not that surprising, really — wealthy philanthropists fund their causes to the level the effort requires, not merely as a way of reducing taxes.

To be clear, we aren’t saying that our messy democracy gets spending right all of the time — or even most of the time. Nor are we critiquing the magnanimity of wealthy philanthropists who choose to bestow some of their accumulated wealth on causes they believe will make us all better off. We just think that if everyone has to pay, everyone should have a say.

Peter B. Bach is the director of the Center for Health Policy and Outcomes at Memorial Sloan Kettering Cancer Center in New York City.