Dave Kopel, Research Director of the Independence Institute writes:

When the PPACA was moving through Congress, there was a lot of bluster from proponents of the law, who insisted that there were absolutely no potential constitutional problems. Most famously, House Speaker Nancy Pelosi scoffed “Are you serious?” to a journalist’s question about the law’s constitutionality.

As it turns out, there are a lot of serious questions.

via Opinion: Affordable Care Act pushes limits of constitutionality | Health Policy Solutions.