Time's run out for net neutrality supporters hoping to restore Obama-era regulations using a legislative loophole, but the fight's far from over as it heads to federal appeals court.

Democrats in the House of Representatives failed to gather enough votes by the end of the year to use the Congressional Review Act to undo the Federal Communications Commission's rollback of the popular rules. The Republican-led agency voted a year ago this month to repeal the rules adopted in 2015, which were designed to ensure that all traffic on the internet was treated equally.

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The FCC, led by Chairman Ajit Pai, an appointee of President Donald Trump, argued that the "heavy-handed" rules deterred internet service providers' investment and innovation. (Read Pai's op-ed on CNET here.)

But supporters of net neutrality say the internet as we know it may not exist much longer without the protections. Big tech companies, such as Google and Facebook, and internet luminaries, such as web creator Tim Berners-Lee, fall into that camp. Since the repeal, they've been working in Congress and in state legislatures to reinstate the rules.

Now these supporters are turning their attention to the courts to save net neutrality.

Attorneys general from 22 states, along with several activist groups and tech companies like Mozilla, have filed suit, accusing the FCC of arbitrarily rolling back the rules and overstepping its authority to ban states from passing their own protections.

The heated legal battle could eventually end up at the Supreme Court, where all eyes will be on the newly appointed Justice Brett Kavanaugh, who questioned the FCC's authority to adopt the original net neutrality protections. That position was expressed in a dissent he wrote last year that challenged the rules.

"I expect the next chapter in the net neutrality story to be mostly about waiting for litigation," said Matt Schettenhelm, a legal analyst with Bloomberg Intelligence.

The legal battle

Legal briefs to the Federal Court of Appeals for the DC Circuit were due in late November, and oral arguments are scheduled for Feb. 1. A decision in the case isn't expected until at least June. But even then, legal experts say, the litigation is unlikely to end.

"The ruling could be appealed 'en banc' to the full DC Circuit, and then to the US Supreme Court," said Schettenhelm. "By the time all that plays out, we'll likely be focused on the 2020 US presidential election."

If the Democrats win the White House, they'll control the FCC again. And that could mean they restore the 2015 net neutrality rules and start the whole process over again.

Two of the big questions being asked in this lawsuit are whether the FCC had sufficient reason to change the classification of broadband so soon after the 2015 rules were adopted and whether the agency has the right to pre-empt states, like California, from adopting their own net neutrality laws.

Schettenhelm said there's a good chance the court will rule in favor of the FCC. There's strong precedent that gives the FCC flexibility in how it interprets the law, evaluates the record and reverses course as it did with the repeal, he said.

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The most effective legal issue for the FCC could be the provision to pre-empt states from creating their own regulations, say experts like Harold Feld of Public Knowledge. The agency has argued that pre-emption is necessary because it would be too complicated for internet service providers to follow different net neutrality rules in 50 states.

More than 30 states introduced legislation in 2018 to make net neutrality state law. Four states -- California, Washington, Oregon and Vermont -- passed laws protecting net neutrality. Several other states, like New York, are considering similar legislation.

States argue that since the FCC has refused to regulate broadband and because the agency abdicated its authority for such regulation to the FTC, they can impose their own rules for services delivered in their states.

California's new law is considered the strictest in the nation because it outlaws some zero-rating offers, such as AT&T's, which exempts its own streaming services -- but not competing products -- from its wireless customers' data caps. The law was supposed to take effect Jan. 1. But in October, the state reached an agreement with the US Department of Justice, which had filed suit against California, not to enforce the law until the bigger question about the FCC's authority to pre-empt states had been answered in the DC Circuit.

What about Congress?

The Congressional Review Act may have failed to reinstate net neutrality regulations, but supporters are hopeful that Democrats, who'll soon control the House of Representatives, will be able to move federal legislation. With a divided Congress, however, and a Republican president who needs to sign off on a new law, it's unclear whether the legislation would include strong enough protections to satisfy net neutrality activists, like a ban on paid priority, or oversight of agreements between network providers that can slow internet access.

"There is more bipartisan consensus on net neutrality than other tech issues," said Matt Wood, policy director for Free Press. "So some kind of net neutrality law is possible. But we'll have to see how far those proposals really go and what they include."

Wood said, though, that a lot of what happens next hinges on the outcome of the lawsuit challenging the repeal.

"I think we'll have to wait and see how the appeals court rules."

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