In the case of Moore v. City of Nampa in 1927, the U.S Supreme Court ruled that a city ordinance requiring door-to-door salespeople to obtain a license was unconstitutional. The plaintiff, Mr. Moore, was an employee for Fuller Brush Company who sold household products door-to-door without obtaining such license from the city of Nampa, Idaho and hence faced prosecution under this local law. He challenged this ordinance arguing it violated his Fourteenth Amendment rights by restricting his ability to engage in lawful trade or business freely across state lines (interstate commerce). The court agreed with him stating that while cities have power to regulate businesses for public safety and welfare purposes; they cannot infrarily restrict interstate commerce which is constitutionally protected at federal level only. Therefore, it struck down the licensing requirement as unconstitutional interference with interstate commerce.

In the dissenting opinion for Moore v. City of Nampa, Justice Stone argued that the majority's decision to uphold a city ordinance prohibiting door-to-door solicitation without prior consent was an infringement on freedom of speech and press. He contended that such ordinances should be subject to strict scrutiny because they potentially infringe upon fundamental rights protected by the First Amendment. According to him, there was no compelling state interest justifying this restriction on free expression in this case as it is not narrowly tailored enough to only restrict harmful or unwanted solicitations but instead broadly bans all forms of door-to-door communication regardless of their nature or purpose. He further pointed out that many socially valuable activities like political campaigning and charitable fundraising rely heavily on door-to-door canvassing which would be unduly burdened by such laws. Therefore, he concluded that unless a clear and present danger can be demonstrated from these activities, any attempt at curtailing them would amount to unconstitutional censorship.