New York state is grappling with a Medicaid shortfall in the billions of dollars. And one of the main reasons is improper enrollment.

Using annual information from the Census Bureau to assess the demographic make-up of Medicaid enrollees over time, researcher Aaron Yelowitz and I estimated that 2.3 million to 3.3 million Medicaid enrollees nationally make an income in excess of what is allowed.

This is of increasing importance given that ObamaCare massively expanded what was historically a welfare program for vulnerable populations like the disabled and low-income children and pregnant women — and tens of billions of taxpayer dollars are at stake.