Article I, Section 9, Clause 3:
No Bill of Attainder or ex post facto Law shall be passed.
As the phrase “ex post facto” ( “after the fact” ) suggests, the Ex Post Facto Clauses apply only to legislation that imposes or increases a punishment retroactively.1 The Ex Post Facto Clauses are related to other constitutional provisions that limit retroactive government action, including the federal and state Bill of Attainder Clauses, the Contract Clause, and the Due Process Clauses.2
In ex post facto cases, the relevant point in time for determining whether a law applies retroactively is the time the offense was committed: the Supreme Court has explained that people must have notice of the possible criminal penalties for their actions at the time they act.3
A key consideration in ex post facto cases is whether the specific individuals challenging the law had notice of all the legal consequences of their actions at the time they committed their offenses. The Supreme Court has rejected ex post facto challenges to laws that might apply retroactively in some circumstances but applied only prospectively to the challengers before the Court.4 The Court has also held that statutes are not retroactive if they apply to past conduct that was also prohibited under a prior statute. For instance, in Harisiades v. Shaughnessy, the Court considered ex post facto claims from several resident aliens who had been ordered deported under a 1940 statute based on their pre-1940 membership in the Communist Party.5 The Court stated that “[a]n impression of retroactivity results from reading as a new and isolated enactment what is actually a continuation of prior legislation.” 6 However, the Court noted that membership in organizations such as the Communist Party had been grounds for deportation since 1920. Thus, the challengers “were not caught unawares by a change of law. There can be no contention that they were not adequately forewarned both that their conduct was prohibited and of its consequences.” 7
The Supreme Court has denied ex post facto challenges to laws that impose legal consequences based not solely on past conduct but rather on an ongoing condition that began in the past. In a late nineteenth century case, Murphy v. Ramsey, the Court rejected an ex post facto challenge to a law that disenfranchised bigamists and polygamists, holding that the law did not retroactively impose a penalty for a crime.8 Although bigamy and polygamy were criminal offenses, the Court observed that the criminal offense was the unlawful marriage itself and was subject to a three-year statute of limitations following the marriage, so that a person subject to disenfranchisement might be “a bigamist or a polygamist, and yet guilty of no criminal offense.” 9
In United States v. Trans-Missouri Freight Association, the Court rejected an ex post facto challenge to the application of an 1890 antitrust law to an agreement begun in 1889.10 The Court explained that the law did not apply to past conduct but rather to an ongoing violation: even if the agreement was lawful when entered into, “the continuation of the agreement, after it has been declared to be illegal, becomes a violation of the act. . . . There is nothing of an ex post facto character about the act.” 11 Similarly, in Samuels v. McCurdy, the Court rejected an ex post facto challenge to a law that prohibited the possession of liquor that was legal when purchased.12 The Court held that the law did not “provide a punishment for a past offense” by penalizing the owner “for having become possessed of the liquor,” but instead imposed a penalty for “continuing to possess the liquor after the enactment of the law.” 13
The Supreme Court has rejected multiple ex post facto challenges to repeat offender statutes on the ground that such statutes do not penalize past conduct.14 In McDonald v. Massachusetts, the Court rejected an ex post facto challenge to a “habitual criminal” statute that imposed an increased penalty for post-enactment offenses based on the defendant’s previous, pre-enactment criminal convictions.15 While the defendant argued that the law amounted to an additional punishment for his prior offenses, the Court concluded that the “statute, imposing a punishment on none but future crimes, is not ex post facto.” 16 The Court likewise approved the consideration of pre-enactment offenses under a repeat offender statute in Gryger v. Burke.17 The Court explained that the sentence for a habitual criminal “is not to be viewed as . . . additional penalty for the earlier crimes. It is a stiffened penalty for the latest crime, which is considered to be an aggravated offense because a repetitive one.” 18
In Johnson v. United States, the Court denied an ex post facto challenge to a statute authorizing courts to impose an additional term of supervised release following the reimprisonment of persons who violate the conditions of an initial term of supervised release.19 The Court declined to construe the statute to apply retroactively and therefore concluded that “the ex post facto question does not arise.” 20
In Kansas v. Hendricks, the Court rejected an ex post facto challenge to a statute allowing for civil commitment of “sexually violent predators,” in part because the statue was not retroactive.21 The Court held that the law allowed for involuntary confinement “based upon a determination that the person currently both suffers from a ‘mental abnormality’ or ‘personality disorder’ and is likely to pose a future danger to the public.” 22 The Court explained that, under the statute, past behavior was permissably used “solely for evidentiary purposes.” 23
- See, e.g., Calder v. Bull, 3 U.S. 386, 391 (1798).
- See, e.g., Fletcher v. Peck, 10 U.S. 87, 138–39 (1810).
- See, e.g., Weaver v. Graham, 450 U.S. 24, 30 (1981) ( “Critical to relief under the Ex Post Facto Clause is . . . the lack of fair notice and governmental restraint when the legislature increases punishment beyond what was prescribed when the crime was consummated.” ).
- Jaehne v. New York, 128 U.S. 189, 194 (1888) (law that might be void as applied to pre-enactment offenses was not void as applied to post-enactment offenses); Bugajewitz v. Adams, 228 U.S. 585, 608–09 (1913).
- 342 U.S. 580, 581–82 (1952).
- Id. at 593.
- 114 U.S. 15, 36 (1885).
- Id. at 43.
- 166 U.S. 290, 342 (1897).
- Id. See also Chicago & Alton R.R. v. Tranbarger, 238 U.S. 67, 73 (1915) ( “[P]laintiff in error is subjected to a penalty not because of the manner in which it originally constructed its railroad embankment, nor for anything else done or omitted before the passage of the act . . ., but because after that time it maintained the embankment in a manner prohibited by that act.” ).
- 267 U.S. 188, 191 (1925).
- Id. at 193.
- Cf. Graham v. West Virginia, 224 U.S. 616, 623 (1912) (upholding repeat offender law against non-ex post facto challenges, holding: “The propriety of inflicting severer punishment upon old offenders has long been recognized in this country and in England. They are not punished the second time for the earlier offense, but the repetition of criminal conduct aggravates their guilt and justifies heavier penalties when they are again convicted.” ).
- 180 U.S. 311, 311 (1901).
- Id. at 313.
- 334 U.S. 728, 729 (1948).
- Id. at 732.
- 529 U.S. 694, 696 (2000).
- Id. at 702.
- 521 U.S. 346, 371 (1997). The Court also held that the statute was not punitive. See ArtI.S9.C3.3.5 Increasing Punishment and Ex Post Facto Laws.