As I noted last week, the lawsuit in which Oklahoma and Nebraska ask the Supreme Court to reverse marijuana legalization in Colorado has prompted criticism from conservatives and libertarians who see it as a betrayal of federalism. Last Wednesday seven state legislators in Oklahoma, all Republicans, echoed that concern in a letter to Attorney General Scott Pruitt. "Oklahoma has been a pioneer and a leader in standing up to federal usurpations of power on everything from gun control to Obamacare and beyond," they write. "We believe this lawsuit against our sister state has the potential, if it were to be successful at the Supreme Court, to undermine all of those efforts to protect our own state's right to govern itself under the Tenth Amendment to the U.S. Constitution."

The legislators argue that the power to "regulate commerce…among the several states," properly understood, does not apply to purely intrastate activity. "For the same reason that alcohol prohibition required a constitutional amendment," they say, "we believe a strong argument can be made that criminalizing and prosecuting drug crimes must be decided at the state level, absent a properly ratified constitutional amendment. If the commerce clause could be interpreted so broadly, there is virtually nothing the federal government could not regulate or control under the guise of 'commerce.'"

But even under the broad reading of the Commerce Clause endorsed by the Supreme Court in Gonzales v. Raich, Congress cannot compel the states to help enforce the federal ban on marijuana. "The lawsuit…appears to endorse federal commandeering of state and local resources to enforce federal statutes and international treaties," the letter says. "We believe the Supreme Court made a wise decision in Printz v United States when it articulated the anti-commandeering doctrine prohibiting the federal government from forcing state and local governments to participate in the enforcement of federal statutes."

Here is how Rep. Mike Ritze (R-Broken Arrow), who organized the letter, explained his motivation:

This is not about marijuana at its core—it is about the U.S. Constitution, the Tenth Amendment, and the right of states to govern themselves as they see fit. If the Supreme Court can force Colorado to criminalize a substance or activity and commandeer state resources to enforce extra-constitutional federal statutes and UN agreements, then it can essentially do anything, and states become mere administrative units for Washington, D.C. That is not what our Founding Fathers had in mind and that is not what the people of Oklahoma stand for. The Constitution reserved the police power to the states, therefore states are the proper venue for determining what their own civil and criminal codes should be, not the federal government or the UN. Our Founding Fathers intended the states to be laboratories of self-government, free to tinker and experiment with different ideas. The founders, from Jefferson to Madison, were also strong proponents of states nullifying unconstitutional federal actions. If the people of Colorado want to end prohibition of marijuana, while I may personally disagree with the decision, constitutionally speaking, they are entitled to do so. Neither the commerce clause nor the supremacy clause grants the federal government the power to regulate intrastate trade or commandeer state and local resources in pursuit of a policy. If citizens of that state don't like it, they are free to use the process to change the laws or move to another state. The last thing we need is the federal government and the UN trying to dictate our criminal codes and control our commercial activities.

Although Ritze's references to the U.N. may seem like rhetorical flourishes aimed at pushing his constituents' buttons, Oklahoma and Nebraska's lawsuit repeatedly cites "treaty obligations" as a reason to override Colorado's policy choices. By contrast, the Obama administration argues that experiments like Colorado's are permitted under an appropriately flexible reading of international anti-drug agreements.

[Thanks to Marc Sandhaus for the tip.]