Prostitution is illegal in the vast majority of the United States as a result of state laws rather than federal laws. It is, however, legal in some rural counties within the state of Nevada. Prostitution nevertheless occurs elsewhere in the country. The regulation of prostitution in the country is not among the enumerated powers of the federal government. It is therefore exclusively the domain of the states to permit, prohibit, or otherwise regulate commercial sex under the Tenth Amendment to the United States Constitution, except insofar as Congress may regulate it as part of interstate commerce with laws such as the Mann Act. In most states, prostitution is considered a misdemeanor in the category of public order crime–crime that disrupts the order of a community. Prostitution was at one time considered a vagrancy crime. Currently, Nevada is the only U.S. jurisdiction to allow legal prostitution – in the form of regulated brothels – the terms of which are stipulated in the Nevada Revised Statutes. Only eight counties currently contain active brothels. All forms of prostitution are illegal in these counties: Clark (which contains the Las Vegas–Paradise metropolitan area), Washoe (which contains Reno), Carson City, Douglas, Eureka, Lincoln & Pershing. The other counties theoretically allow brothel prostitution, but three of these counties currently have no active brothels. Street prostitution, "pandering", and living off of the proceeds of a prostitute remain illegal under Nevada law, as is the case elsewhere in the country. According to the National Institute of Justice, a study conducted in 2008 alleged that approximately 15-20 percent of men in the country have engaged in commercial sex. As with other countries, prostitution in the U.S. can be divided into three broad categories: street prostitution, brothel prostitution, and escort prostitution. History 18th century Some of the women in the American Revolution who followed the Continental Army served the soldiers and officers as sexual partners. Prostitutes were a worrisome presence to army leadership, particularly because of the possible spread of venereal diseases (in modern terms, sexually transmitted infection or STI). 19th century In the 19th century, parlor house brothels catered to upper class clientele, while bawdy houses catered to the lower class. At concert saloons, men could eat, listen to music, watch a fight, or pay women for sex. Over 200 brothels existed in lower Manhattan. Prostitution was illegal under the vagrancy laws, but was not well-enforced by police and city