This is the Cato Daily Podcast for Tuesday, July 29, 2014.

I'm Caleb Brown.

Rand Paul would like to see the federal government respect the authority of states that

have legalized cannabis for medical purposes.

Cato Vice President for Legal Affairs Roger Pillan would go one further.

You'd like to see the feds recognize that the federal drug war has no sound footing in the Constitution at all.

President Obama made sort of a big deal out of the idea that he would not be having the federal police enforce marijuana laws, federal marijuana laws in states

that had approved medical marijuana and then spent several years going back on that and in some ways

more vigorously enforcing those laws. That's right and it has raised along with other things that he has done the question

whether he he is violating his constitutional duty to see that the laws be faithfully executed, a charge that has come from

both libertarians and conservatives recently, especially with respect to Obamacare. This is just one more example of that problem, but it's

much more complicated than that and it's been addressed recently or is being addressed by a measure that Senator Rand Paul has introduced that would allow people who sell, use, doctors who were involved in, the commercial sale of marijuana for especially medical purposes in now some 33 states

apparently to be immune from prosecution and one can be sympathetic to that but it does raise very

interesting federalism issues that I'd be glad to go into. The place to start is probably with the idea that criminal law is

under our system primarily a state function, murder, rape, and robbery are prosecuted for the most part by the states

because there is no federal criminal police power of a general sort that belongs to the states.

And so the first question that arises that how is that the federal government gets involved

in this at all? Well it turns out that the federal government gets involved in this at all?

Well it turns out that the drug laws are passed under the Commerce Clause,

not under any federal power to prosecute crime. That raises real problems in itself because the

Commerce Clause was designed to ensure the free flow of commerce among the

states and what this does is prohibit the free flow of

...