"Act for the Suppression of Trade in, and Circulation of, Obscene Literature and Articles for Immoral Use"
The Comstock Law, passed in the United States in 1873, was part of a campaign for legislating public morality in the United States.
As its full title (above) implies, the Comstock Law was meant to stop the trade in "obscene literature" and "immoral articles."
In reality, the Comstock Law was targeted not only at obscenity and "dirty books" but at birth control devices and information on such devices, at abortion, and at information on sexuality and on sexually transmitted diseases.
The Comstock Law was widely used to prosecute those who distributed information or devices for birth control. In 1938, in a case involving Margaret Sanger, Judge August Hand lifted the federal ban on birth control, effectively ending the use of the Comstock Law to target birth control information and devices.