The International Megan's Law to Prevent Child Exploitation and Other Sexual Crimes Through Advanced Notification of Traveling Sex Offenders (H.R. 515) is a federal law that requires, among other things, a visual "unique identifier" to be placed on the passports of registrants convicted of sex offenses involving a minor. The law also requires covered offenders to notify law enforcement 21 days before traveling abroad. Critics have claimed violation of constitutional rights and note that the law would also cover those who were convicted as minors.