... the result might arise that as a consequence of the striking down of a discriminating clause, a right of suffrage would be enjoyed by reason of the generic character of the provision which would remain after the discrimination was stricken out.[487] 171. Both the States and the United States are forbidden by the Constitution to enact _ex post facto_ laws. The prohibition affects every citizen as securing him from the peril of legislation of the kind forbidden. It is a sweeping limitation of power for his or her benefit, and operates for all citizens of whatever age, condition, or circumstance. An _ex post facto_ law is one that makes an action done before the passing of the law, and which was innocent when done, criminal, and punishes that action; that aggravates a crime, or makes it greater than it was when committed; that changes the punishment and inflicts a greater punishment than the law annexed to the crime when committed; that alters the legal rules of evidence, and receives less or different testimony than the law required, at the time of the commission of the offense, in order to convict the offender. But no law is _ex post facto_ within the constitutional prohibition that “mollifies the rigor of the criminal law.” Only those laws are _ex post facto_ which “create, or aggravate the crime, or increase the punishment, or change the rules of evidence, for the purpose of conviction.”[488] 172. But he who, under State law, voluntarily waived his right of trial by jury and elected to be tried by the court and by it was adjudged guilty and was condemned to be hanged, was not deprived of any right, privilege, or immunity for his protection by the Fourteenth Amendment, but was tried and condemned in strict accordance with the forms prescribed by the constitution and laws of the State, and with special regard to the rights of accused persons under its jurisdiction.[489] A person may waive a fundamental right[490] but neither the State nor the United States can lawfully invade the indefeasible right of a person to personal security[491]; such invasion constitutes an “unwarrantable search and seizure.” The service of a lawful warrant operates practically as a waiver of right by the person searched or seized; but were a person to waive his right, say of trial by jury, such waiver would not confer power on any court or jury to try him. “Consent can never confer jurisdiction.”[492] 173. Am act of Congress that no person shall be excused from attending and testifying, or from producing books, papers, tariffs, contracts, agreements, and documents before the Interstate Commerce Commission, or in obedience to its subpœna, on the ground that he might thus be compelled to be a witness against himself and so become subject to penalty is constitutional because its additional provision immuning him from future prosecution by reason of his evidence thus given sufficiently satisfies the constitutional guarantee of protection.[493]