In accordance with article 5, section XXXVI of the Brazilian Constitution, laws concerning acquired rights, legal acts performed and legal force may not have retroactive effects. Article 9.3 of the Spanish Constitution guarantees the non-retroactivity of penal provisions that do not promote or restrict the rights of the individual. Therefore, «a posteriori» criminal laws or other retroactive penal provisions are prohibited by the Constitution. In Sweden, retroactive criminal sanctions and other retroactive legal effects of offences to which the State is entitled are prohibited under Article 10 of Chapter 2 of the Regeringsformen. Retroactive taxes or levies are not prohibited, but they can only go back retroactively to the time when a new tax law was proposed by the government. The retroactive effect of a tax or levy therefore extends from that moment until the bill is passed by Parliament. Article 1 of the Penal Code stipulates that no act is punishable without a pre-existing law and that in the event that an act was punishable but the law was amended after the crime, the «more favourable» (for the suspect) of the two laws applies. [30] In administrative law, federal agencies can apply their rules retroactively if Congress has authorized them to do so; Otherwise, retroactive application is generally prohibited. The retroactive application of the rules is rejected by the courts for several reasons. The courts will maintain retroactive rules if Congress has expressly granted the agency such retroactive power as they did in Bowen v. Georgetown University Hospital.

[49] Another example of ex post facto criminal law in the UK is the Criminal Justice Act 2003. This law allows persons acquitted of murder and certain other serious crimes to be retried if there is «new, convincing, reliable and substantial evidence» that the acquitted person was genuinely guilty. This law applies retroactively and can be used to re-prosecute persons who were acquitted before its entry into force in 2005 or even before its adoption in 2003. As a result, two of the defendants acquitted in the murder of Stephen Lawrence were allowed to be retried, even though that murder took place in 1993 and the defendants were acquitted in 1996. Many people have criticized the Criminal Justice Act for its substantial abolition of the prohibition of ex post facto and dual criminality laws. [37] The Indonesian Constitution prohibits in all circumstances the conviction of citizens under retroactive laws. This was put to the test in 2004 when the conviction of Masykur Abdul Kadir, one of the Bali attackers, was overturned under retroactive counter-terrorism legislation. [27] The U.S. Supreme Court (the Court) has again ruled that new decisions in criminal cases cannot be applied retroactively to the review of federal safeguards, even if convictions have been obtained in violation of the Constitution. The Court has not seen new codes of criminal procedure that could ever be applied retroactively. In its opinion of 17. In May 2021, in Edwards v.

Vannoy (Edwards), she noted that the continued suggestion that there could be cases in the future where retroactive application of a new rule or decision is possible gives litigants false hopes of a reversal, «distorts the law, misleads judges and the resources of defense lawyers, Prosecutors and courts. Finally, in Calder v. Ex-post facto, laws are expressly prohibited by the U.S. Constitution in Section 1, Section 9, clause 3 (with respect to federal statutes) and Section 1, Section 10 (with respect to state laws). In some countries that follow the Westminster system of government, such as the United Kingdom, ex post facto laws are possible because the doctrine of parliamentary supremacy allows Parliament to pass any desired law. In a country with a well-established bill of rights or a written constitution, ex post facto legislation may be prohibited. Retroactive application of the law is prohibited by Article 3 of the Polish Civil Code, and the rule of law prohibiting such retroactive application is usually remembered as the Latin expression Lex retro non agir («A law does not apply retroactively»). However, this section allows for the retroactive application of an Act of Parliament if it is expressly understood from its text or purpose. Retroactive legislation to prosecute what was perceived as a grossly unethical means of tax avoidance was passed by the Fraser government in the early 1980s (see Tax Avoidance at the Bottom of the Port). Similarly, legislation retroactively criminalizing certain war crimes has been found to be constitutional (see Polyukhovich v.

Commonwealth). An ex post-facto law (corrupted from Latin: ex postfacto, lit. «of the suite») is a law that retroactively modifies the legal consequences (or status) of acts committed before the promulgation of the law or relationships that existed. In criminal law, it can criminalize acts that were lawful at the time they were committed; it may aggravate a crime by placing it in a more serious category than it was at the time it was committed; it may change the penalty imposed for a criminal offence, for example by adding new penalties or extending the penalties; or it may change the rules of evidence to make a conviction for a crime more likely than would have been the case when the crime was committed.