Late Friday, a federal judge granted a preliminary injunction in the lawsuit EFF filed with the ACLU of Northern California (ACLU-NC) that challenges the unconstitutional provisions in Proposition 35, a ballot measure passed by California voters in November that restricts the legal and constitutionally protected speech of all registered sex offenders in California.

EFF and the ACLU-NC filed the lawsuit the morning after Election Day, noting that although Prop 35 is ostensibly about increasing punishment for human traffickers, it’s beset with problems. The biggest was its requirement that registrants turn over a list of all their Internet identifiers and service providers to law enforcement. The court granted a temporary restraining order hours after the lawsuit was filed. And today, the court granted the preliminary injunction, finding we were likely to succeed in showing that Prop. 35 violated the First Amendment.

First, the court found that there was a clear chilling effect on speech because registrants would have to disclose their identity either before they speak, or within 24 hours after speaking somewhere online. Plus, without any safeguards to prevent the public dissemination of this online identification information — and the potential three-year prison term awaiting a registrant for failing to comply — the court was convinced registrants would think twice before speaking.

The court also found that Prop. 35 applied “both to more speakers and more speech” than necessary to advance the government interest in combatting human trafficking. Prop. 35 requires anyone who is a registered sex offender — even people with decades-old, low-level offenses like misdemeanor indecent exposure and people whose offenses were not related to the Internet — to report this information. That would cover more than 75,000 Californians. And it required a wide range of information, including email addresses, usernames and other identifiers used for online political discussion groups, book and restaurant review sites, forums about medical conditions, and newspaper or blog comments, to be turned over to the government. While the government claimed at a hearing last month they only intended to use the information if it had a “nexus” to a criminal investigation, the court found that “nexus” to be missing from the text of Prop. 35 at all. As a result, the court believed registrants' “right to speak anonymously will therefore be chilled.”

Noting that registrants “enjoy no lesser right to anonymous speech simply because they are ‘unpopular,’” the Court concluded that a “requirement that sex offenders report to the government all communications on blogs and websites puts a stake through the heart of the First Amendment’s protection of anonymity and surely deters faint-hearted offenders from expressing themselves on matters of public concern.”

We’re pleased the Court recognized the serious First Amendment problems with Prop. 35. Requiring people — even unpopular people — to give up their ability to speak freely and anonymously chills everyone’s free speech. Allowing the government to monitor and record a wide swath of innocent Internet activity, from a registrant with a fantasy football team to someone who comments on a political discussion group, is a dangerous trend that can easily expand, as law enforcement’s inevitable thirst for information fails to be quenched. By pushing back against this well-intentioned but ultimately misguided law, the court is doing its part to ensure that free speech is alive and well on the Internet.