Article I, Section 9, Clause 3:

No Bill of Attainder or ex post facto Law shall be passed.

Congress and state legislatures sometimes enact temporary statutes that apply until a fixed expiration date. In United States v. Powers, the Supreme Court held that a legislature may extend a temporary criminal statute before it expires, and that, following the extension, the government may prosecute pre-extension conduct—that is, conduct that occurred while the temporary law was in effect and expected to expire as initially planned—without violating the Ex Post Facto Clause.1 The Court explained that, due to the extension at issue in that case, “the Act has never ceased to be in effect. No new law was created; no old one was repealed. Without hiatus of any kind, the original Act was given extended life.” 2

In Dobbert v. Florida, a prisoner sentenced to death raised a claim that “there was no ‘valid’ death penalty in effect in Florida as of the date of his actions” because the state had made subsequent changes to sentencing procedures to satisfy newly articulated constitutional requirements.3 The prisoner committed two murders between December 1971 and April 1972. In July 1972, the Florida Supreme Court found that the state’s death penalty statute was inconsistent with the requirements laid out Furman v. Georgia.4 Florida enacted new death penalty procedures in late 1972, and the challenger was convicted and sentenced under the new regime. The prisoner argued that the death penalty statute in effect at the time of his crimes had been struck down, and that applying the new statute to his conduct was ex post facto. The Supreme Court rejected that claim, holding that despite its procedural flaws, the old statute had “clearly indicated Florida’s view of the severity of murder and of the degree of punishment” appropriate to that crime.5

By contrast, the Supreme Court has held that a legislature may not retroactively reimpose criminal liability after it has lapsed. Many criminal laws contain statutes of limitations that bar prosecution once a certain amount of time passes after an offense is committed. In Stogner v. California, the Court held that “a law enacted after expiration of a previously applicable limitations period violates the Ex Post Facto Clause when it is applied to revive a previously time-barred prosecution.” 6 The Court explained that a law extending a statute of limitations after it had lapsed falls within the second category of ex post facto laws laid out in Calder, a “law that aggravates a crime, or makes it greater than it was, when committed,” because it “inflict[s] punishments, where the party was not, by law, liable to any punishment.” 7

Footnotes

1

307 U.S. 214, 216 (1939).

2

Id. at 217.

3

432 U.S. 282, 297 (1977).

4

408 U.S. 238 (1972).

5

Dobbert, 432 U.S. at 297.

6

539 U.S. 607, 632–33 (2003).

7

Id. at 614–615.