Over the last few decades, the number of federal crimes has exploded. The U.S. criminal code has grown so large and so expansive that no one is exactly sure how many federal crimes are actually on the books, with estimates ranging from 4,000 to 300,000. As Justice Scalia has noted, “It should be no surprise that as the volume increases, so do the number of imprecise laws.” Many individuals and organizations from across the ideological spectrum have voiced concern over this growing trend, recognizing that broadly defined crimes lack the clarity traditionally required before depriving citizens of their liberty. The expansion of 18 U.S.C § 1001, which criminalizes the knowing and willful making of materially false statements in “any matter within the jurisdiction of” the United States, exemplifies this broadening scope. Cory King was prosecuted under this statute for making a false statement to a state official wholly unconnected to any federal agency or investigation. Yet, the Ninth Circuit held that Mr. King violated § 1001 because the subject matter of his statement was one over which a federal government agency possessed regulatory authority. King has now asked the Supreme Court to hear his case; Cato has joined the National Association of Criminal Defense Lawyers and the Texas Public Policy Foundation on a brief supporting him and arguing that the Ninth Circuit stretched § 1001 beyond its proper jurisdictional reach. Such an unbounded interpretation risks greater over criminalization and further misuse of the federal criminal code. Moreover, since § 1001 is a “process crime” that focuses on offenses “not against the particular person or property, but against the machinery of justice itself,” an excessively broad construction would undermine the integrity of the criminal justice system. Wider application of such crimes facilitates pretextual prosecutions, in which “the operating philosophy seems to be that, if the government cannot prosecute what it wished to penalize, it will penalize what it can prosecute.” Such an arbitrary and far-reaching application of the criminal code—the federal criminal code, at that—has no place in a free society.