A top Washington trade group for Internet companies such as Dropbox, Facebook and Netflix is now defending federal regulators in a major court battle over net neutrality, adding a legal brief to the flurry from both sides of the debate.

Arguing that the FCC acted legally when it rolled out strong new rules for broadband companies this year, the Internet Association said Monday that the regulations help protect consumers from Internet providers who control access to the Web. The "friend-of-the-court" filing called for the FCC's net neutrality order to be fully upheld — endorsing for the first time the legal approach the FCC used to implement its regulations.

"Consumers and innovators will benefit from the Internet openness promoted by the FCC’s net neutrality Order," it reads.

Opponents of the rules, such as AT&T and the National Cable and Telecommunications Association, filed a lawsuit against the agency in April. They're arguing that the FCC overstepped its authority in designing its net neutrality policy, and are calling for the rules to be overturned by the court.

The FCC's net neutrality policy subjects Internet providers such as AT&T, Comcast and Verizon to some of the same rules that govern legacy telephone service in the United States. The move was hotly contested by industry amid fears of an administrative power grab that critics said would lead to the government's direct involvement in setting retail prices for Internet.

The FCC's rules also regulate providers of cellular data in similar ways — a move that the wireless industry argues is illegal. But Internet Association president Michael Beckerman said the FCC used its authority properly.

"Internet access has changed over the past few years," said Beckerman. "My expectations are now the same whether I'm accessing the Internet from my mobile device or from my home computer."

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