Yes.
The case will have significance in explaining just what Congress’ powers are when it comes to passing laws.
As we all remember from civics class, we live in a system of joint sovereignty: state governments are sovereign, but share sovereignty with the federal government.
The state has plenary police power: basically, like a King, the state can legislate in any area it pleases. The federal government is limited in powers to only those that the Constitution grants it.
However, in those areas where the federal government does have power, its power can eclipse the states’ power, so the state actually can’t legislate in “any area it pleases.” It can only legislate where its powers don’t conflict with the granted powers of the federal government.
Congress’ list of powers are supreme overt the states because the Supremacy Clause in Article VI of the Constitution says so:
So when Congress makes a law under the powers given by the Constitution, that law trumps any state law. No surprise there.
But what about this “treaty” thing? You’ll notice that the laws Congress makes must be under Congress’ congressional powers: (“…the Laws of the United States which shall be made in Pursuance [of the Constitution…]”) Congress can’t just make any law they please - it can only be laws that implement Congress’ granted powers. But the treaty business has no such exception: a treaty gets to become the supreme law of the land as long as Congress agrees to it, with no mention of any limits on subject matter.
In 2005, a woman named Carol Anne Bond discovered that her husband had impregnated her best friend. Furious, she vowed revenge. She worked at a chemical processing plant, and used her access at work to teal toxic chemicals. She purchased other chemicals online, mixed them into a toxic paste, and applied that paste liberally to her former best friend’s mail, mailbox, front doorknob, car door, and other convenient targets. Fortunately for Myrlinda Haynes, the erstwhile friend, the toxic paste was bright orange and easily avoidable; she suffered only a burnt finger. But she was upset, and reported these actions to the local police, who inexplicably declined to take any action. She then involved the U.S. Postal Service, pointing out that her mail had been a target, and postal inspectors set up a camera and caught Bond in the act.
Federal prosecutors charged Bond with violating the Chemical Weapons Convention, which bans the unauthorized use or storage of dangerous chemicals. Normally, this is not a crime Congress could reach – the Constitution doesn’t give Congress the power to criminalize chemicals that are used locally. (It’s certainly possible Congress could criminalize these chemicals because they had moved in interstate commerce – but they didn’t.)
But the United States did sign the Chemical Weapons Convention, a treaty intended to limit chemical weapons use by countries, and to enforce the rules of the treaty, Congress passed a law criminalizing the unauthorized use or storage of toxic chemicals. Bond was prosecuted and convicted under this law.
On appeal, she claims that this is unfair: the state had a law against what she did. She should have been prosecuted by the state, she argues. (The maximum sentence she could have gotten from the state was much less than the federal sentence.)
Further, she says, Congress can’t just make any law they please simply because a treaty says so. That would lead to the absurd result that all those so-called “limits” on Congress’ power are illusions: Congress can get around them by making a treaty. She points to the Tenth Amendment, which specifically says that the powers not given directly to Congress under the Constitution belong to the states, or the people. She says that if Congress can get around that reservation of power to the states with a treaty, the Tenth Amendment means nothing, which is an illogical result.
The United States says that not only is the Constitution clear, but that the Supreme Court has already answered this very question: almost a hundred years ago, in Missouri v. Holland, the Court ruled that a treaty protecting migratory bids gave Congress the power to makes laws about the killing of wild birds, a power that is not otherwise mentioned in the Constitution and thus would be reserved to the states.
So: there are two parts to the Constitution that appear to conflict with each other: the Tenth Amendment and the Supremacy Clause.
The Court’s decision in this sordid love triangle story could have far-reaching effects on Congress’ powers.