ArtI.S9.C3.2 Ex Post Facto Laws

Article I, Section 9, Clause 3:

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

Both federal and state governments are prohibited from enacting ex post facto laws,1 and the Court applies the same analysis whether the law in question is a federal or a state enactment. When these prohibitions were adopted as part of the original Constitution, many persons understood the term ex post facto laws to embrace all retrospective laws, or laws governing or controlling past transactions, whether . . . of a civil or a criminal nature.2 But in the early case of Calder v. Bull,3 the Supreme Court decided that the phrase, as used in the Constitution, was a term of art that applied only to penal and criminal statutes. But, although it is inapplicable to retroactive legislation of any other kind,4 the constitutional prohibition may not be evaded by giving a civil form to a measure that is essentially criminal.5 Every law that makes criminal an act that was innocent when done, or that inflicts a greater punishment than the law annexed to the crime when committed, is an ex post facto law within the prohibition of the Constitution.6 A prosecution under a temporary statute that was extended before the date originally set for its expiration does not offend this provision even though it is instituted subsequent to the extension of the statute's duration for a violation committed prior thereto.7 Because this provision does not apply to crimes committed outside the jurisdiction of the United States against the laws of a foreign country, it is immaterial in extradition proceedings whether the foreign law is ex post facto or not.8

What Constitutes Punishment

The issue of whether a law is civil or punitive in nature is essentially the same for ex post facto and for double jeopardy analysis.9 A court must ascertain whether the legislature intended the statute to establish civil proceedings. A court will reject the legislature’s manifest intent only where a party challenging the Act provides the clearest proof that the statutory scheme is so punitive in either purpose or effect as to negate the State’s intention.10 A statute that has been held to be civil and not criminal in nature cannot be deemed punitive as applied to a single individual.11

A variety of federal laws have been challenged as ex post facto. A statute that prescribed as a qualification for practice before the federal courts an oath that the attorney had not participated in the Rebellion was found unconstitutional because it operated as a punishment for past acts.12 But a statute that denied to polygamists the right to vote in a territorial election was upheld even as applied to one who had not contracted a polygamous marriage and had not cohabited with more than one woman since the act was passed, because the law did not operate as an additional penalty for the offense of polygamy but merely defined it as a disqualification of a voter.13 A deportation law authorizing the Secretary of Labor to expel aliens for criminal acts committed before its passage is not ex post facto because deportation is not a punishment.14 For this reason, a statute terminating payment of old-age benefits to an alien deported for Communist affiliation also is not ex post facto, for the denial of a non-contractual benefit to a deported alien is not a penalty but a regulation designed to relieve the Social Security System of administrative problems of supervision and enforcement likely to arise from disbursements to beneficiaries residing abroad.15 Likewise, an act permitting the cancellation of naturalization certificates obtained by fraud prior to the passage of the law was held not to impose a punishment, but instead simply to deprive the alien of his ill-gotten privileges.16

Change in Place or Mode of Trial

A change of the place of trial of an alleged offense after its commission is not an ex post facto law. If no place of trial was provided when the offense was committed, Congress may designate the place of trial thereafter.17 A law that alters the rule of evidence to permit a person to be convicted upon less or different evidence than was required when the offense was committed is invalid,18 but a statute that simply enlarges the class of persons who may be competent to testify in criminal cases is not ex post facto as applied to a prosecution for a crime committed prior to its passage.19


  1.  Jump to essay-1The prohibition on state ex post facto legislation appears in Art. I, § 10, cl. 1.
  2.  Jump to essay-23 J. Story, Commentaries on the Constitution of the United States 1339 (1833).
  3.  Jump to essay-33 U.S. (3 Dall.) 386, 393 (1798).
  4.  Jump to essay-4Bankers Trust Co. v. Blodgett, 260 U.S. 647, 652 (1923).
  5.  Jump to essay-5Burgess v. Salmon, 97 U.S. 381 (1878).
  6.  Jump to essay-6Calder v. Bull, 3 U.S. (3 Dall.) 386, 390 (1798); Ex parte Garland, 71 U.S. (4 Wall.) 333, 377 (1867); Burgess v. Salmon, 97 U.S. 381, 384 (1878).
  7.  Jump to essay-7United States v. Powers, 307 U.S. 214 (1939).
  8.  Jump to essay-8Neely v. Henkel, 180 U.S. 109, 123 (1901). Cf. In re Yamashita, 327 U.S. 1, 26 (1946) (dissenting opinion of Justice Murphy); Hirota v. MacArthur, 338 U.S. 197, 199 (1948) (concurring opinion of Justice Douglas).
  9.  Jump to essay-9Kansas v. Hendricks, 521 U.S. 346 (1997); Seling v. Young, 531 U.S. 250 (2001).
  10.  Jump to essay-10Seling v. Young, 531 U.S. 250, 261 (2001) (interpreting Art. I, § 10).
  11.  Jump to essay-11Seling v. Young, 531 U.S. at 263 (2001).
  12.  Jump to essay-12Ex parte Garland, 71 U.S. (4 Wall.) 333 (1867).
  13.  Jump to essay-13Murphy v. Ramsey, 114 U.S. 15 (1885).
  14.  Jump to essay-14Mahler v. Eby, 264 U.S. 32 (1924); Bugajewitz v. Adams, 228 U.S. 585 (1913); Marcello v. Bonds, 349 U.S. 302 (1955). Justices Black and Douglas, reiterating in Lehman v. United States ex rel. Carson, 353 U.S. 685, 690–91 (1957), their dissent from the premise that the ex post facto clause is directed solely to penal legislation, disapproved a holding that an immigration law, enacted in 1952, 8 U.S.C. § 1251, which authorized deportation of an alien who, in 1945, had acquired a status of nondeportability under pre-existing law is valid. In their opinion, to banish, in 1957, an alien who had lived in the United States for almost 40 years, for an offense committed in 1936, and for which he already had served a term in prison, was to retrospectively subject him to a new punishment.
  15.  Jump to essay-15Flemming v. Nestor, 363 U.S. 603 (1960).
  16.  Jump to essay-16Johannessen v. United States, 225 U.S. 227 (1912).
  17.  Jump to essay-17Cook v. United States, 138 U.S. 157, 183 (1891).
  18.  Jump to essay-18Calder v. Bull, 3 U.S. (3 Dall.) 386, 390 (1798).
  19.  Jump to essay-19Hopt v. Utah, 110 U.S. 574, 589 (1884).