The ACA mandate was challenged in federal courts by Republican state Attorneys General. On June 28, 2012, the U.S. Supreme Court upheld the provision as Constitutional. Chief Justice John Roberts delivered the majority opinion in National Federation of Independent Business v. Sebelius, which upheld the Patient Protection and Affordable Care Act by a 5 - 4 vote. The Court ruled that although the "individual mandate '' component of the act was not constitutional under the Commerce Clause, it was reasonably construed as a tax and was therefore valid under the Congressional authority to "lay and collect taxes. ''
which constitutional power of congress was used to establish the individual mandate under obamacare
to "lay and collect taxes. ''