Ignacio Flores-Figueroa was an illegal alien from Mexico living the United States. He was convicted of two cases of aggravated identify theft
The case was brought to the Supreme Court, where they determined that Flores-Figueroa's argument was valid. They determined that the government must prove the mens rea requirement of identify theft, that is that the government must prove that the defendant "knowingly" used another person's identify (in this case, Social Security Number and alien registration number) to constitute an aggravated felony
The case is particularly interesting in immigration law due to the common use of fake identification for illegal aliens. It also proves that immigration law, while its own entity, affects other aspects of law as well. Criminal law, in this case identify theft law, is impacted by immigration law. The decision showed that the modifier "knowingly" should apply to all elements of a crime, as determined by ordinary grammatical rules. This case also brings up another point related to the mens rea requirement.
Justice Antonin Scalia wrote a separate opinion stating that the Court should distinguish between cases using the mens rea requirement when Congress has not addressed it in language and cases where Congress as purposely limited the requirement for specific elements of a crime. Additionally, it affirmed that the mens rea requirement of a federal statute should apply to every element of the crime. In immigration law, the decisions distinguished between identify theft and the use of fake identification.
According to the Supreme Court, prosecutors could no longer use federal identify-theft law against illegal workers utilizing fake Social Security numbers. The removal of this particular weapon is important in immigration law because it would make immigration enforcement change their strategy in pressing criminal charges against immigrants guilty only of working illegally.