Can the government try someone twice for the same offense? Usually, no. Double jeopardy is the constitutional protection that bars the government from prosecuting or punishing a person more than once for the same crime after an acquittal, a conviction, or, in some situations, after a case has been resolved and jeopardy has legally attached. It comes from the Fifth Amendment to the U.S. Constitution and is also protected by Article I, Section 12 of the Iowa Constitution. The rule is aimed at preventing repeated prosecutions, multiple punishments for the same offense, and the strain of being forced to defend the same criminal accusation over and over.

In practice, whether double jeopardy applies often turns on timing and on whether the later case is truly for the "same offense." A dismissed charge may sometimes be refiled if jeopardy never attached. A mistrial may or may not block another prosecution. Separate sovereigns can also complicate things, because a state case and a federal case are not always treated as the same prosecution.

For injury claims, double jeopardy usually does not stop a civil lawsuit. A person can face a criminal case after a crash or assault and still be sued in civil court for damages by the injured person. In Iowa, that civil claim is generally controlled by the two-year statute of limitations in Iowa Code section 614.1(2) (2024), which is separate from any double-jeopardy issue in the criminal case.