In Pursuing Johns, Thomas C. Mackey studies the New York Committee of Fourteen and its members’ attempts to influence vagrancy laws in early-20th-century New York City as a way to criminalize men’s patronizing of female prostitutes. It sought out and prosecuted the city’s immoral hotels, unlicensed bars, opium dens, disorderly houses, and prostitutes. It did so because of the threats to individual “character” such places presented. In the early 1920s led by Frederick Whitin, the Committee thought that the time had arrived to prosecute the men who patronized prostitutes through what modern parlance calls a “john’s law.” After a notorious test case failed to convict a philandering millionaire for vagrancy, the only statutory crime available to punish men who patronized prostitutes, the Committee lobbied for a change in the state’s criminal law. In the process, this representative of traditional 19th-century purity reform allied with the National Women’s Party, the advanced feminists of the 1920s. Their proposed “Customer Amendment” united the moral Right and the feminist Left in an effort to alter and use the state’s criminal law to make men moral, defend their character, and improve New York City’s overall morality. Mackey’s contribution to the literature is unique. Instead of looking at how vice commissions targeted female prostitutes or the commerce supporting and surrounding them, Mackey concentrates on how men were scrutinized.