Cornell law professor Sherry F. Colb comments on a decision the U.S. Supreme Court issued toward the end of the last term, in which a majority of the Court ruled that as long as police have probable cause for an arrest, it does not matter if their actual motivation for arresting someone violates the person’s First Amendment rights. Colb considers whether such pretextual, speech-based arrests are a problem, how they differ from other pretextual arrests, and how the ruling in this case resembles the law of a seemingly different area—post-conviction incarceration for convicted criminals.