The final question courts must resolve in double jeopardy litigation is determining whether successive prosecutions or punishments are for the "same offense." Jeopardy may have already attached and terminated in a prior criminal proceeding, but the state may bring further criminal action against a person so long as it is not for the same offense. Courts have analyzed this question in several ways, depending on whether the state is attempting to re-prosecute a defendant or impose multiple punishments.

At common law a single episode of criminal behavior produced only one prosecution, no matter how many wrongful acts may have been committed during that episode. But over the last fifty years the proliferation of overlapping and related offenses has made it possible for the government to prosecute someone for several different crimes stemming from the same set of circumstances. For example, an individual who has stolen a car to facilitate an abduction resulting in attempted rape could be separately prosecuted and punished for auto theft, kidnapping, and molestation. This development has significantly enlarged prosecutors' discretion over the charging process.

The Supreme Court curbed this discretion in Blockburger v. United States, 284 U.S. 299, 52 S.Ct. 180, 76 L.Ed. 306 (1932). The Court said that the government may prosecute an individual for more than one offense stemming from a single course of conduct only when each offense requires proof of a fact the other does not. Blockburger requires courts to examine the elements of each offense as they are delineated by statute, without regard to the actual evidence that will be introduced at trial. The prosecution has the burden of demonstrating that each offense has at least one mutually exclusive element. If any one offense is completely subsumed by another, such as a lesser included offense, the two offenses are deemed the same, and punishment is allowed only for one.