EX POST FACTO LAW. A statute which would render an act punishable in a manner in which it was not punishable when it was committed. 6 Cranch, 138 ; 1 Kent, Comm. 408. A law made to punish acts committed before the existence of such law, and which had not been declared crimes by preceding laws. Mass. Deelar. of Rights, pt. 1, s. 24 ; Md. Declar. of Rights, art. 15.
2. By the constitution of the United States, congress is forbidden to pass ex post facto laws. U. S. Const. art. 1, 9. And by 10, subd. 1, of the same instrument, as well as by the constitutions of many, if not all, of the states, a similar restriction is imposed upon the state legislatures. Such law is void as to those cases in which, if given effect, it would be ex post ,facto; but so far only. In cases arising under it, it may have effect ; for as a rule for the future it is not ex post facto.
3. There is a distinction between ex post facto laws and retrospective laws: every ex post facto law must necessarily be retrospec tive, but every retrospective law is not an ex post facto law i the former only are pro hibited.
It is fully settled that the term ex post facto, as used in the constitution, is to be taken in a limited sense as referring to criminal or penal statutes alone, and that the policy, the reason, and the humanity of the prohibition against passing ex post facto laws do not ex tend to civil cases, to cases that merely affect the private property of citizens. Some of the most necessary acts of legislation are, on the contrary, founded upon the principles that private rights must yield to public exigencies. 3 Dall. Penn. 386 ; 8 Wheat. 89;
17 How. 463 ; 6 Cranch, 87 ; 8 Pet. 88 ; 11 id. 421. See 1 Cranch, 109 ; 9 id. 374; 1 Gall. C. C. 105 ; 2 Pet. 380, 523, 627 ; 3 Story, Const. 212; Sergeant, Const. Law, 356 ; 2 Pick. Mass. 172 ; 11 id. 28 ; 9 Mass. 363 ; 2 Root, Coon. 350 ; 5 T. B. Monr. Ky. 133 ; 1 J. J. Marsh. Ky. 563 ; 3 N. H. 475 ; 7 Johns. N. Y. 488; 6 Binn. Penn. 271 ; 2 Pet. 681 ; RETROSPECTIVE.
4. Laws under the following circumstances are to be considered ex post facto laws within the words and intent of the prohibition : 1. Every law that makes an act done before the passing of the law, and which was innocent when done, criminal, and punishes such action. 2. Every law that aggravates a crime, or makes it greater than it was when committed. 3. Every law that changes the punishment, and inflicts a greater punish ment than the law annexed to the crime when committed ; though it would be other wise of a law mitigating the punishment. 3 Story, Const. 212. 4. Every law that alters the legal rules of evidence, and receives less or different testimony than the law required at the time of the commission the offence, in order to convict the offender ; though it might be otherwise of a law merely modifying the remedy or mode of procedure. 3 Dall. Penn. 390. See RETROSPECTIVE.