The Federal Communications Commission voted Thursday to dismantle its net neutrality regulations. But that won’t end the fight over rules that prohibit internet service providers from creating fast lanes for some content, while blocking or throttling others.

Most immediately, the activity will move to the courts, where the advocacy group Free Press, and probably others, will challenge the FCC’s decision. The most likely argument: that the commission’s decision violates federal laws barring agencies from crafting “arbitrary and capricious” regulations. After all, the FCC’s net neutrality rules were just passed in 2015. Activists and many members of Congress, including at least six Republicans, pushed for a delay in the vote, but apart from a brief delay due to a security issue, the vote occurred as planned.

But as capricious as the current FCC's about-face may seem, legal experts say the challenges won’t be a slam-dunk case. Federal agencies are allowed to change their minds about previous regulations, so long as they adequately explain their reasoning. "It's not carte blanche," says Marc Martin, chair of law firm Perkins Coie’s communications practice. "You can't make it obvious that it's just based on politics." Martin says the burden of proof will be on net neutrality advocates challenging the agency.

The FCC's main argument for revoking the 2015 rules is that the regulations hurt investment in broadband infrastructure. But, as WIRED recently detailed, many broadband providers actually increased their investments, while those that cut back on spending told shareholders that the net neutrality rules didn't affect their plans.

University of Pennsylvania Law School professor Christopher Yoo says courts generally defer to an agency's expertise in interpreting evidence submitted into the record. "Courts generally side with agencies on those types of issues," Yoo says.

Martin says net neutrality advocates could also argue that the agency's decision-making process was corrupted by the flood of fake comments left by bots. But FCC Chair AJit Pai will argue that the agency discarded low-quality and repeated comments and focused only on matters of substance, which Martin says may well be enough to sway a court.

Beyond the Courts

Broadband providers say the public has nothing to worry about. AT&T, Comcast, and Verizon, among others, have promised not to block or throttle content. But those promises leave internet providers with quite a bit of room to prioritize their own content, or content from their partners.

AT&T, for example, already allows its DirecTV Now video-streaming service to bypass mobile subscribers’ data limits. Verizon does much the same with its Go90 video service. Sling TV and Netflix, on the other hand, still count towards customers’ data caps. The end of the FCC’s current rules will allow companies to expand the ways they prioritize certain services over others.

Harold Feld of the advocacy group Public Knowledge recommends that people concerned with net neutrality keep a watchful eye on internet providers and file complaints about prioritizing or throttling with the Federal Trade Commission and the Department of Justice, though those agencies won’t have the broad authority that the FCC has under the 2015 rules. He also thinks it's worth fighting for state-level laws to protect net neutrality, even though the FCC's order blocks states from making their own net neutrality rules. Martin and Feld both think courts might throw out that provision of the FCC's order even if they uphold the rest.

Just about everyone agrees that the real future of net neutrality will be decided in Congress. Free Press, Demand Progress, and other groups are pushing Congress to overturn the FCC’s decision to revoke the net neutrality rules; the group suggests Congress do this by a joint resolution, the same legal framework it employed earlier this year to undo internet-privacy rules the FCC adopted last year.