http://www.fcc.gov/cgb/consumerfacts/obscene.html
Obscene speech is not protected by the First Amendment and cannot be
broadcast at any time. To be obscene, material must meet a three-prong test:
-An average person, applying contemporary community standards, must find that the material, as a whole, appeals to the prurient interest;
-The material must depict or describe, in a patently offensive way, sexual conduct specifically defined by applicable law; and
-The material, taken as a whole, must lack serious literary, artistic, political, or scientific value.