In a ruling that imposes important limits on the FCC's authority to regulate the Internet, the D.C. Circuit Court of Appeals today overturned the FCC ruling against Comcast for interfering with the BitTorrent traffic of its subscribers. The court found that the Commission had overstepped the limits of its "ancillary authority" when it disciplined Comcast for its clandestine blocking behavior.

The ruling is not likely to make much difference to Comcast subscribers—Comcast had already agreed to cease its BitTorrent interdiction before the FCC's ruling was issued. Instead, the court's ruling is important because it represents a blow to FCC Chairman Genachowski's proposed net neutrality regulations, which are premised on the same theory of "ancillary jurisdiction" that the FCC used against Comcast and that the court rejected today.

Here's the problem: Congress has never given the FCC any authority to regulate the Internet for the purpose of ensuring net neutrality. In place of explicit congressional authority, the FCC decided to rely on its "ancillary jurisdiction," a catchall source of authority that amounts to “we can regulate without waiting for Congress so long a the regulations are related to something else that Congress told us to do.” Of course, this line of reasoning could translate into carte blanche authority for unelected bureaucrats to regulate the Internet long after Chairman Genachowski has moved on. As we put it in October:

If “ancillary jurisdiction” is enough for net neutrality regulations (something we might like) today, it could just as easily be invoked tomorrow for any other Internet regulation that the FCC dreams up (including things we won’t like). For example, it doesn't take much imagination to envision a future FCC "Internet Decency Statement." After all, outgoing FCC Chairman Martin was a crusader against "indecency" on the airwaves and it was the FCC that punished Pacifica radio for playing George Carlin’s “seven dirty words” monologue, something you can easily find on the Internet. And it's also too easy to imagine an FCC "Internet Lawful Use Policy," created at the behest of the same entertainment lobby that has long been pressing the FCC to impose DRM on TV and radio, with ISPs required or encouraged to filter or otherwise monitor their users to ensure compliance. After all, it was only thanks to a jurisdictional challenge ... that we defeated the FCC's "broadcast flag" mandate which would have given Hollywood and federal bureaucrats veto power over innovative devices and legitimate uses of recorded TV programming.

So while we are big supporters of net neutrality, we are glad that today's ruling has reasserted the important limits on the FCC's authority to regulate the Internet.

The fight now moves back to Congress and the FCC, with numerous net neutrality advocates urging the FCC to "reclassify" Internet access services under Title II of the Communications Act—another effort to find FCC authority to regulate ISPs without having to go to Congress. In the meantime, everyone who cares about net neutrality will continue to watch ISPs closely for more evidence of discriminatory practices.