New research about implementation of the Affordable Care Act finds that Obama administration regulations are allowing taxpayer subsidized health insurance for some people earning less than the statutory income floor and also for unlawful immigrants.

A new study by Andy S. Grewal, an associate professor at the University of Iowa College of Law, explains that the ACA provides tax credits to U.S. citizens with incomes between 100 and 400% of the Federal Poverty Level (FPL). However, IRS regulations were written to extend credits to citizens below 100% FPL in some cases.

Also, Section 36B of the ACA grants credits to some non-citizens with low-incomes only if they are themselves lawfully present in the U.S. and cannot obtain Medicaid coverage. IRS regulations, however, contradict the statute and allow subsidies if “the taxpayer or a member of the taxpayer’s family is lawfully present in the United States,” and “the lawfully present taxpayer or family member is not eligible for the Medicaid program.”