Broadcasters, film studios and news directors are among a group of parties that has filed suit to block Federal Communications Commission rules that limit “indecent” programming to between midnight and 6 a.m.

The suit, filed this week in the D.C. Court of Appeals, claims that the indecency rules violate the First Amendment rights of media groups by “reducing adults to seeing and hearing material fit only for children.” The petitioners asked the court to delay the Feb. 24 effective date of the rules until their case can be heard.

The FCC adopted the indecency regs last week under orders from Congress. Lawmakers voted overwhelmingly last year in favor of the midnight to 6 a.m. indecency ban, and attached the measure to a popular public broadcasting funding bill. The rules affect radio and TV broadcasters but not cable TV operators.

Congress and the FCC have argued that the rules are needed to prevent unsupervised children from viewing indecent programming. Opponents of the new rules are given a good shot at having them overturned, however, since the D.C. appellate court has twice tossed out similar restrictions against racy programming.

The media orgs claim the regs are unnecessary, since adults are usually at home to monitor the viewing habits of children. They also argue that adults will be “deprived … of access to material protected by the First Amendment” if indecent programs are channeled solely into the hours of midnight to 6 a.m.

“A news report that involved arguably indecent material would lose its timeliness if not broadcast until many hours after the fact,” the media groups argued. “And quality dramatic or satiric programs on mature themes would no longer be economically justifiable if they could be presented only to the small post-midnight audience.”

The media groups also criticize a quirky aspect of the new rules that permits public broacasters to air indecent programming from 10 p.m. to midnight–but only if the station goes off the air at midnight. Commercial broadcasters signing off at midnight are not given the same option, a provision that the petitioners claim is discriminatory.

The media groups also ask the court to bar the FCC from imposing indecency sanctions on programming that has no “appreciable audience of unsupervised children under age 12.”

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