• by Wendy Davis , Staff Writer @wendyndavis, March 20, 2014

Sen. Al Franken (D-Minn.), one of the most vocal proponents of net neutrality principles, is warning the Department of Justice that Comcast's planned acquisition of Time Warner could threaten the open Internet.

“The Internet is an open marketplace where everyone can participate on equal footing, regardless of one’s wealth or influence,” he writes in a letter sent to the DOJ this week. “Comcast’s proposed acquisition of Time Warner Cable could disrupt this balance of power, resulting in higher costs and fewer choices for consumers.”

He adds that neutrality principles prohibit companies like Comcast from “picking and choosing which lawful Internet content will reach homes and offices across the country.”

The Federal Communications Commission passed neutrality rules in 2010, but an appellate court struck down the regulations earlier this year. The regulations would have prohibited wireline broadband providers from blocking, degrading or discriminating against lawful sites and apps.

The FCC is in the process of crafting new rules, but for now broadband providers appear free to censor sites at will. Comcast, however, is an exception. That's because the company agreed to follow neutrality rules through 2018, as a condition of its NBC Universal acquisition.

Franken acknowledged Comcast's obligations in his letter to the DOJ, but pointed out that what will happen after 2018 remains an open question. The lawmaker also is raising questions about Comcast's paid peering arrangements, like a recent deal that allows Netflix to connect directly to Comcast's network. Peering isn't considered a net neutrality issue, but Franken says the practice still raises competitive concerns.

“By acquiring Time Warner Cable, Comcast would extend its reach substantially, covering millions of additional customers,” Franken writes. “This would give Comcast even more leverage to manipulate Internet traffic to serve its own corporate interests.”