Attorneys Robert Henneke and Chance Weldon argue in a Daily Caller column that recent changes challenge the Affordable Care Act‘s constitutionality.

In 2012, the five conservative justices on the United States Supreme Court (including Chief justice John Roberts) held that key portions of the Affordable Care Act (ACA) exceeded Congress’s constitutional authority under the Commerce Clause. But, Chief Justice Roberts then joined the four liberal justices on the Court in upholding the ACA as a tax under Congress’s taxing power because it generated revenue for the federal government.

Fast forward five years: In 2017, the Republican-majority Congress did not have the votes to repeal the ACA but did set the individual mandate penalty at zero. In doing so, Congress eliminated the Court’s sole constitutional justification for upholding the ACA — a tax of zero is not a tax.

Texas and nineteen other states recently sued challenging the current constitutionality of the ACA. Individuals subject to the ACA mandates, represented by the Texas Public Policy Foundation, also joined this lawsuit. The parties argue that because the ACA individual mandate penalty no longer generates revenue, it is no longer a tax; therefore, Chief Justice Robert’s justification upholding the law no longer applies, leaving the ACA now unconstitutional — just like the five conservative justices have already opined.

It seems pretty straightforward.