The Volokh Conspiracy

Mostly law professors | Sometimes contrarian | Often libertarian | Always independent

About The Volokh Conspiracy Editorial Independence Who we are Books Volokh Daily Email Archives Search DMCA RSS

Immigration

The Greater the Illegal Migrant Population, the Stronger the Case Against Mass Deportation

Cato Instiute immigration expert David Bier explains why.

Ilya Somin | 8.18.2026 6:01 PM

People hold up "mass deportation now" signs at the 2024 Republican National Convention. (Carol Guzy/ZUMAPRESS/Newscom)

Standard estimates of the illegal/undocumented immigrant population in the United States range from about 11 million to 15 million. But right-wing immigration restrictionists often assert the true figure is much higher, as with Donald Trump's  claim that it is 25 million. The implicit assumption is that the higher the number, the stronger the case for mass deportation. But, as my Cato Institute colleague David Bier - a leading immigration policy expert - explains in a recent article (fuller, but paywalled version here) the exact opposite is true:

The math is simple. The more illegal immigrants, the more Americans would have to pay to deport them. The Department of Homeland Security estimates that a single deportation costs on average $18,245. This means that when Trump invents the presence of 10 million more immigrants, he's adding a theoretical $182.4 billion to the price tag.

And that's just the cost of deportation. The cost to federal revenue is even starker. Illegal immigrants pay sales tax — and, often, Social Security tax, income tax and property tax. The more illegal immigrants we deport, the more the cost of funding........

© Reason.com