The United States Postal Service (plaintiff) prohibits the solicitation for alms and contributions on postal premises. Marsha Kokinda and Kevin Pearl (defendants) were volunteers for the National Democratic Policy Committee who set up a table on the sidewalk near the entrance of a Maryland Post Office to solicit contributions, sell books and newspaper subscriptions, and distribute literature addressing a variety of political issues. Kokinda and Pearl were asked to leave the premises, and refused. They were arrested and convicted of violating the Postal Service regulation. Kokinda and Pearl challenged their convictions on the grounds that the regulation violated the First Amendment, but the federal district court denied relief. The court of appeals reversed finding that the sidewalk in front of the Post Office was a traditional public forum and the governmental regulation failed strict scrutiny. The United States Supreme Court granted certiorari.