Some laws are not designed to limit freedom of expression, but nevertheless can have that effect. For example, when a National Park Service regulation prohibiting camping in certain parks was applied to prohibit demonstrators, who were attempting to call attention to the plight of the homeless, from sleeping in certain Washington, D.C. parks, it had the effect of limiting the demonstrators’ freedom of expression. Nevertheless, the U.S. Supreme Court found that application of the regulation did not violate the First Amendment because the regulation was content-neutral and was narrowly focused on a substantial governmental interest in maintaining parks “in an attractive and intact condition.”