Hanni Fakhoury, a lawyer at the Electronic Frontier Foundation, an Internet civil rights group that has joined the A.C.L.U. in the lawsuit, said the law reflected government attempts to strengthen limits on sex offenders and regulate the Internet. Sex offenders, he said, should be guaranteed First Amendment rights in both physical and digital spheres.
“Online speech is very different in form than traditional speech,” Mr. Fakhoury said. “But in substance, they should be treated the same under the First Amendment.”