Most of the laws passed by the modern Congress are rooted in the Commerce
Clause of the Constitution. The Supreme Court has ruled that the constitutional
definition of interstate commerce is very broad: anything that moves between
the states, or any business that uses raw materials that come from out of state
are considered interstate commerce. For example, a barbecue restaurant
whose only customers were local instate residents was found to be involved in
interstate commerce because it bought food and condiments that originated
outside the state. Although the delivery of medical services to individual
patients is a local activity, everything that medical care practitioners use, from
drugs to bandages to the paper that the medical records are written on, comes
from other states. The courts have repeatedly found medical care businesses
to be subject to regulation as interstate commerce.
Although the states have ceded the power to regulate interstate commerce to
the federal government, they retained, via their police powers, the right to
regulate any activity that poses a threat to the public health or safety of their
citizens. Thus, state laws that seek to ban the import of milk from outside the
state to protect local dairies are an unconstitutional attempt to control trade.
In contrast, state laws that focus on consumer protection, such as requiring the
sanitary inspection of imported milk and banning the import of contaminated
milk, are constitutional, provided they also apply to milk produced within the
state. This distinction between laws affecting commerce and laws affecting
health and safety is important to medical care practitioners because the
regulation of the practice of medicine is considered a health and safety issue
and thus reserved to the states as a police power.