In Central Hudson Gas & Elec. Corp. v. Public Serv. Commn. (447 US 557 [1980]), the Supreme Court adopted a four-part test for determining the validity of government restrictions on commercial speech, as distinguished from more fully protected speech: (1) the First Amendment protects commercial speech only if that speech concerns lawful activity and is not misleading. a restriction on otherwise protected commercial speech is valid only if it; (2) seeks to implement a substantial governmental interest; (3) directly advances that interest; (4) reaches no further than necessary to accomplish the given objective. (447 US, at 563-566.)