Whether the Fourteenth Amendment's Due Process Clause permits conviction for failing to comply with a felony-registration ordinance when the defendant had no actual knowledge of the duty and the prosecution made no showing that she probably knew of it.
Holding
No. Due process bars conviction under this ordinance absent actual knowledge of the duty to register or proof of the probability of such knowledge followed by a failure to comply.
Reasoning
The Court acknowledged that legislatures have broad authority to create public-welfare offenses that do not require proof of intent or knowledge. The traditional rule that ignorance of the law ordinarily does not excuse remains deeply rooted. But that authority is not unlimited: due process imposes a notice requirement in appropriate circumstances.
Lambert's alleged offense was wholly passive. She did not engage in an act that would naturally alert an ordinary person to legal regulation; her liability arose solely from remaining in Los Angeles without registering. Unlike regulatory and licensing laws tied to business activity or affirmative conduct, this ordinance made mere presence in the city the trigger for criminal punishment.
Nothing about Lambert's circumstances supplied a reason to inquire about a registration obligation. The ordinance served chiefly as a law-enforcement device for compiling the names and addresses of people with prior felony convictions, information that was already a matter of public record. Yet once Lambert learned of the requirement through prosecution, she had no opportunity to register and avoid punishment for an innocent default.
Due process requires notice when government imposes penalties for a failure to act, and that principle applies with special force when criminal punishment is imposed on a person who was unaware of any wrongdoing. Treating an uninformed person as criminally liable in these circumstances would be comparable to enforcing a law printed too finely to read or written in a language foreign to the community.