More than half a dozen advocacy groups ranging from liberal to libertarian agree on one thing: the proposal for a porn-free national broadband service put forth by Federal Communications Commission Chair Kevin Martin is "unconstitutional and unwise."

The Friday filing illustrates the plan as a "government mandated 'blacklist' of websites."

The filtering system would restrict the system "so dramatically that the usefulness of the service would be radically reduced."

Additionally, it's a strong possibility that the agency would receive a maelstrom of lawsuits if the proposal comes to fruition.

The method Martin hopes to employ has taken heavy criticism from the wireless community citing technical deficiencies.

The disgruntled public interest groups include the Center for Democracy and Technology, Adam Thierer of the Progress and Freedom Foundation, the Public Interest Spectrum Coalition, People for the American Way, the Von Coalition, the Electronic Frontier Foundation, the American Booksellers Association and 15 others.