At the end of March, the U.S. Supreme Court heard six hours of oral arguments regarding the health care reform law. At the center of the debate was the law’s individual mandate, which, beginning in 2014, will require all individuals to purchase health care insurance or pay a penalty.

Opponents of the law argue that an individual mandate is unconstitutional because it forces people to engage in commerce. Proponents maintain that health care is distinguished from other forms of commerce in ...