Last week, during his visit to Mexico, administration officials confirmed that Pres. Obama will push the U.S. Senate to ratify the “Inter-American Convention Against the Illicit Manufacturing of and Trafficking in Firearms, Ammunition, Explosives, and Other Related Materials.” The Clinton administration signed the treaty after the Organization of American States adopted it in 1997. The Administration’s nominee for Legal Adviser to the State Department, Harold Koh, has praised the Convention. This praise is misguided, and raises questions about Koh’s commitment to free speech around the world, and his willingness to provide aid and comfort to foreign tyrants.

Koh has been a staunch advocate of the Convention. In 2002, he praised it as providing “the best model” for his favorite goal of promoting “the legal, political and social internalization of . . . [an] emerging international norm [against illicit arms transfers] into domestic legal systems.” Koh neglected to mention that, though the U.S. has signed the Convention, the Senate has not ratified it, an omission characteristic of his dismissive treatment of the role of the Senate in the treaty-making process. He also argues that the Convention requires states “to standardize national laws.” On the contrary, the Convention explicitly recognizes that, because “states have developed different cultural and historical uses for firearms,” a standardized model is unacceptable.

But these points aside, much of the Convention, as we have already noted, is uncontroversial, sensible, and fully in accord with U.S. practice. Indeed, as the administration acknowledges, the U.S. already abides by it in spirit. But the Convention also has troubling elements. Chief among these is its provision requiring all signatories to criminalize the “counseling” of the commission of the illicit manufacturing of, or trafficking in, firearms. The Convention makes this an extraditable offense. Finally, the Convention requires states to afford each other “the widest measure of mutual legal assistance . . . in order to obtain evidence and take other necessary action to facilitate procedures and steps involved in . . . investigations or prosecutions.”

Two elements of this are troubling. First, the requirement to criminalize “counseling” is an attack on free speech. If this provision were put into effect, it would become a crime, for instance, to say that the Venezuelan people, or the Cuban people, should import or manufacture arms to resist their tyrannical governments. The Convention does allow that, for reasons of “constitutional principles,” not all states may be able to criminalize speech in this way. Presumably, that restriction applies to the U.S.

But this conflict between the Convention and the Constitution would have to be interpreted by the U.S. courts. One can never know what such an interpretation will produce. The safe rule is a simple one: the U.S. should never sign treaties that criminalize speech, or that conflict in other ways with the Constitution. In any case, many states will be entirely able to criminalize “counseling.” In effect, the Convention provides international legal cover and justification for denying the right of speaking of armed rebellion against oppression. The U.S. cannot be true to the rebellion that began in 1776 and endorse this principle, here or abroad.

Second, the requirement to afford “mutual legal assistance” could easily be put to bad use. In most cases, the U.S. will naturally want to assist foreign authorities, to the extent allowed by law: the American presumption should, for instance, always be in favor of assisting Canada, as democratic state. But not all the Convention’s signatories are democratic. Venezuela, for instance, headed by President Obama’s new best friend Hugo Chavez, is an OAS member and a Convention signatory.

Under the Convention, if a Venezuelan exile in the U.S. counseled the Venezuelan people to resist Chavez, he could be charged with a crime in Venezuela. The U.S. would then be obliged to afford the Venezuelan authorities assistance in gathering evidence, investigating, and prosecuting this ‘crime.’ Venezuela would also have the right to request the extradition of the ‘suspect.’ The U.S. could refuse this request on political grounds, but this could be deemed a violation of both the Convention and the existing extradition treaty between the U.S. and Venezuela.

In the end, the U.S. would simply have to refuse to uphold treaties it had signed in good faith. This would be necessary in this case, but it is not sound practice. And it certainly conflicts with Koh’s belief that “responsible lawyers, scholars, and human rights activists” should use the U.S. court system to force the U.S. to comply with all international law, whether the U.S. has signed and ratified it or not. Under Koh’s vision, a U.S. court would be obligated to enforce the Convention, even if it was being used as an instrument of oppression by a foreign power.

In short, the Convention is a poorly drafted document that, along with much that is unproblematic, contains provisions that conflict with the Constitution, would make the U.S. party to the repression of speech abroad, and would require the U.S. to either break its own pledges or give aid and comfort to foreign dictators by assisting their investigation of dissidents in the U.S.

Having endorsed the Convention whole-heartedly, Koh must have considered and dismissed all of these points. Let us hope that when he, and the Convention, appear before the Senate Foreign Relations Committee, the members of the U.S. Senate are less willing than Koh to substitute advocacy of international law for analysis of the ways in which it can be put to evil uses.