The Trump-era FCC repealed net neutrality earlier this year and it has become a political issue. All that remained was for California Governor Jerry Brown to sign the bill into law, which he did on Sunday. In a court filing for an injunction, the Justice Department said that companies "cannot realistically comply with one set of standards in this area for California and another for the rest of the nation - especially when Internet communications frequently cross multiple jurisdictions".
Led by Scott Wiener (D-California), lawmakers met with little resistance in pushing through Senate Bill 822, which prohibits internet service providers from blocking or slowing down websites or "whole classes of applications", like video.
Advocates of net neutrality hope California's law will push Congress to enact national rules or encourage other states to create their own.
USA attorney general Jeff Sessions said in a statement that "states do not regulate interstate commerce - the federal government does", after California became the largest state to enact its own rules requiring internet providers to treat all web traffic equally.
Pai said he was "pleased" to see the federal government's lawsuit, and that "The Internet is free and open today, and it will continue to be under the light-touch protections of the FCC's Restoring Internet Freedom Order".
Many conservatives and FCC Chairman Ajit Pai have also spoken out against net neutrality, arguing it would do more harm than good.
The DOJ is not the only ones moving to stop this new law. The new rules took effect in June but providers have made no changes in access.
State Sen. Connie Leyva (D), who introduced the bill, lamented Brown's veto and said she would re-introduce the legislation in 2019.
In August, 22 states and a coalition of trade groups representing major tech companies urged a federal appeals court to reinstate the rules.
Disregarding the clear popular support for such protections and showing its commitment to seeing net neutrality destroyed, the Trump administration immediately sued California after Gov. "Net neutrality, at its core, is the basic notion that we each get to decide where we go on the internet, as opposed to having that decision made for us by internet service providers". Brown called the bill "unnecessary", noting that abortions are a "long-protected right in California".
But to justify the law, California would also need to prove that its existing laws and powers aren't enough to protect consumer welfare on net neutrality, said Berin Szóka, president of the think tank TechFreedom and a critic of the legislation.