WASHINGTON -- A melodramatic love triangle begot a ham-handed revenge poisoning. That led to what one justice called an "unimaginable" federal prosecution of the scorned wife under a law enacted to implement a global chemical weapons treaty.
And that, in turn, led Tuesday to a grand constitutional showdown at the U.S. Supreme Court that at times seemed emblematic of the nation's long-running political debate over the limits of federal power.
At the center of the case is a question of when the federal government may intrude on powers traditionally given to the states -- in this case, police powers. And a majority of justices bristled at Solicitor General Donald Verrilli's argument that courts have little place to question that intrusion when it takes the form of legislation passed by Congress to carry out a treaty.
Justice Samuel Alito said most people would be "flabbergasted" to know how federal prosecutors used the law targeting terrorists who use chemical weapons to go after Carol Anne Bond, a suburban Philadelphia microbiologist.
Ms. Bond, who cannot have children, was outraged in 2006 when she learned that her best friend, Myrlinda Haynes, was pregnant by Ms. Bond's husband, Clifford. Ms. Bond ordered a rare blend of chemicals, partly off the Internet, and over the next several months tried to poison Ms. Haynes 24 times by putting them on her doorknob, car and, critically, mailbox.
Ms. Haynes suffered nothing more than a burn on her fingers, and local prosecutors would not pursue charges. They suggested that she call in the feds, and postal inspectors set up surveillance that identified Ms. Bond as her assailant.
Federal prosecutors charged Ms. Bond with violating the 1998 Chemical Weapons Convention Implementation Act, a law based on the chemical weapons ban treaty signed by all but four of the world's nations.
Ms. Bond pleaded guilty while reserving the right to appeal her conviction. The case has been through so many courts -- there was a prior Supreme Court stop -- that she has completed her prison term (and, lawyers say, reunited with her husband).
She is represented by former Bush administration solicitor general Paul Clement, who also faced Mr. Verrilli in the court's most recent high-profile battle over the limits of congressional power: the 2012 challenge to the Affordable Care Act.
Mr. Clement, going first, said that if the law implementing the treaty "really does reach every malicious use of chemicals anywhere in the nation, as the government insists," then it violates the "bedrock principle of our federalist system that Congress lacks a general police power to criminalize conduct" that lacks a distinctly federal concern.
Mr. Clement's problem was that the court ruled in 1920, in a decision by Justice Oliver Wendell Holmes, that while "the great body of private relations usually fall with the control of the state, a treaty may override its power."
Justice Ruth Bader Ginsburg said no one disputes that the treaty is valid, and that the law the treaty required Congress to pass largely follows its specifications. "So, it's a puzzle that the treaty could be constitutional, but the implementing legislation that adds nothing is unconstitutional," she said.
Mr. Clement said the difference, which separates it from the 1920 precedent, is that the chemical arms treaty doesn't directly regulate individual conduct.
But Justice Elena Kagan, picking up the battle, told Mr. Clement that the treaty directed that legislation be passed regarding individuals.