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The open internet is losing one of its strongest supporters in Congress as Sen. Al Franken, a Democrat from Minnesota, plans to resign amid allegations of sexual misconduct.

Franken made the announcement Thursday after multiple women had accused him of inappropriately touching them or forcibly trying to kiss them. In a statement on the Senate floor, Franken apologized for the behavior but denied some of the claims.

"Let me be clear, I may be resigning my seat but I am not giving up my voice," Franken said. "I will continue to stand up for the things I believe in as a citizen and as an activist."

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Franken, who was a cast member on "Saturday Night Live" before serving in the Senate for eight years, was one of the most high-profile and vocal members of Congress on key tech and media issues. He was notably a strong supporter for stricter rules on net neutrality, the concept that companies have to treat all internet traffic equally.

His looming departure comes as the Federal Communications Commission is set to roll back the existing net neutrality rules in the name of removing regulations on companies to spur investment.

Franken was also one of the key opponents and critics of the trend of continued consolidation, including Comcast's acquisition of NBCUniversal.

He was one of the key figures on the Senate Intelligence Committee who grilled Facebook, Google and Twitter over Russia's influence over the elections and our political discourse. He was particularly heated over the companies' willingness to take Russian rubles for ads, and could be counted on for a sharp jab.

"You can't put together rubles with a political ad and say, 'Hmm, those two data points spell something bad?'" he asked during a hearing in October.

Net neutrality

Franken's contributions to the net neutrality fight will remain one of the legacies of his Senate career. He was one of the first leaders in Congress to push for stronger net neutrality regulation, publicly advocating for it in 2009 when he questioned then-nominee for the US Supreme Court Sonia Sotomayor. Franken has described net neutrality as the most important free speech issue of our time.

He criticized the FCC's first attempt at writing net neutrality regulation in 2010, calling the rules weak because they didn't ban paid prioritization, which he believed would allow broadband companies to charge companies like Netflix a fee to access their customers faster than other competitors. In 2011, he and Sen. Maria Cantwell, a Democrat from Washington, introduced legislation that would have put strong net neutrality protections into law.

A federal appeals court eventually tossed out the FCC's 2010 rules and instructed the agency to go back to the drawing board. The result was the 2015 rules, which banned broadband companies from offering paid prioritization and also reclassified broadband as a public utility, which gave the FCC greater authority to regulate broadband networks.

The current FCC under Republican control will vote next week to roll back these rules and will strip the FCC of its authority to regulate the internet. Franken has said this is a mistake.

"The internet is really basic to the First Amendment," he said in an interview in July with CNET. "And it doesn't matter if it's the FCC or Congress that provides those protections. It just needs to be protected."

More recently, Franken pushed the idea that companies like Facebook and Google should also follow similar nondiscrimination rules as internet service providers. Currently, the FCC's regulatory authority only includes network operators, but Franken has argued these internet companies also act as monopolies and shouldn't be allowed to block or slow access to content.

"As tech giants become a new kind of Internet gatekeeper, I believe the same basic principles of net neutrality should apply here: No one company should have the power to pick and choose which content reaches consumers and which doesn't," Franken wrote last month in an op-ed for The Guardian. "Facebook, Google, and Amazon—like ISPs—should be 'neutral' in their treatment of the flow of lawful information and commerce on their platforms."

The movement goes on

Net neutrality supporters say they are grateful for Franken's commitment to an open internet. But they say the fight will continue without him.

"Sen. Franken was an outspoken champion in the Senate for net neutrality, but obviously not the only one," said Matt Wood, policy director of Free Press. "Dozens of lawmakers -- and most importantly, millions of people -- have stood up to protect crucial communications rights."

Wood added that as important as internet freedoms and free speech are, the sexual harassment issues had to be dealt with.

"I don't want to take any attention away from those issues for a second," he said. "But net neutrality never has been about one senator or even a handful of them, it's a fundamental protection for everyone."

Democrats have a strong bench of net neutrality supporters on Capitol Hill willing to go to bat for the cause, such as Sen. Charles Schumer of New York, Sen. Ed Markey of Massachusetts and Sen. Brian Schatz of Hawaii. It's also expected that Minnesota Gov. Mark Dayton will appoint someone to fill Franken's seat who will also support net neutrality regulation.

"Net neutrality is a core issue for Democrats," said Gigi Sohn, an adviser to the former FCC Chairman Tom Wheeler, who drafted the 2015 rules. "We're already seeing candidates for 2018 campaigning on the issue."

First published Dec. 7, 9 a.m. PT.

Updated, 12:09 p.m. PT: Adds information about Franken's support of net neutrality and comments from net neutrality proponents.

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