Source: https://caselaw.findlaw.com/us-supreme-court/269/167.html
Timestamp: 2019-04-24 19:18:22+00:00

Document:
[269 U.S. 167, 168] Messrs. Province M. Pogue and Harry M. Hoffheimer, both of Cincinnati, Ohio, for plaintiff in error Beazell.
Mr. Frank F. Dinsmore, of Cincinnati, Ohio, for plaintiff in error Chatfield.
Mr. John Wilson Brown, III, of Washington, D. C., for defendants in error.
It is settled, by decisions of this court so well known that their citation may be dispensed with, that any statute which punishes as a crime an act previously committed, which was innocent when done, which makes more burdensome the punishment for a crime, after its commission, or which deprives one charged with crime of any defense available according to law at the time when the act was committed, is prohibited as ex post [269 U.S. 167, 170] facto. The constitutional prohibition and the judicial interpretation of it rest upon the notion that laws, whatever their form, which purport to make innocent acts criminal after the event, or to aggravate an offense, are harsh and oppressive, and that the criminal quality attributable to an act, either by the legal definition of the offense or by the nature or amount of the punishment imposed for its commission, should not be altered by legislative enactment, after the fact, to the disadvantage of the accused.
Expressions are to be found in earlier judicial opinions to the effect that the constitutional limitation may be transgressed by alterations in the rules of evidence or procedure. See Calder v. Bull, 3 Dall. 386, 390; Cummings v. State of Missouri, 4 Wall. 277, 326; Kring v. Missouri, 107 U.S. 221, 228 , 232 S., 2 S. Ct. 443. And there may be procedural changes which operate to deny to the accused a defense available under the laws in force at the time of the commission of his offense, or which otherwise affect him in such a harsh and arbitrary manner as to fall within the constitutional prohibition. Kring v. Missouri, 107 U.S. 221 , 2 S. Ct. 443; Thompson v. Utah, 170 U.S. 343 , 18 S. Ct. 620. But it is now well settled that statutory changes in the mode of trial or the rules of evidence, which do not deprive the accused of a defense and which operate only in a limited and unsubstantial manner to his disadvantage, are not prohibited. A statute which, after indictment, enlarges [269 U.S. 167, 171] the class of persons who may be witnesses at the trial, by removing the disqualification of persons convicted of felony, is not an ex post facto law. Hopt v. Utah, 110 U.S. 575 , 4 S. Ct. 202, 28 8l. Ed. 262; nor is a S. 575, 4 S. Ct. 202; nor is a after the indictment so as to render admissible against the accused evidence previously held inadmissible, Thompson v. Missouri, 171 U.S. 380 , 18 S. Ct. 922; or which changes the place of trial, Gut v. Minnesota, 9 Wall. 35; or which abolishes a court for hearing criminal appeals, creating a new one in its stead. See Duncan v. Missouri, 152 U.S. 377, 382 , 14 S. Ct. 570.

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