• by Wendy Davis  @wendyndavis, June 28, 2016

Airbnb is asking a federal judge to prohibit San Francisco from enforcing a measure that would require the company to police the listings on its site.

Since February of 2015, San Francisco has required people who rent their homes on a short-term basis to register with the city. Two weeks ago, the city passed a new measure that requires companies like Airbnb to verify that users who post ads have valid registration numbers. Airbnb says the verification procedure requires it to disclose to the city the names and addresses of everyone who is advertising apartments. The law also imposes civil and criminal penalties on companies that fail to monitor their sites for violations.

Airbnb argues that the new measure -- which effectively requires the company to police its listings -- violates the Communications Decency Act. That law immunizes Web platforms from liability for users' activity.

"A fundamental purpose of Congress in passing the CDA was to shield website operators from compulsory obligations to screen user content upon pain of liability, and instead to provide them with the incentive to build innovative platforms while having the flexibility to experiment with and develop tools to address undesirable content without fear of legal retribution," the company argues in a motion filed this week in federal court in San Francisco.

Airbnb also says the verification provisions violate the federal Stored Communications Act, which requires the government to obtain subpoenas or warrants before demanding information about users from Web sites.

The company argues in its legal papers that federal courts throughout the country have invalidated laws that would have required online classifieds site Backpage.com to police its listings. For instance, in 2013 a federal judge in Tennessee permanently barred the state from enforcing a law regulating online ads. That law, aimed at curbing the sex-trafficking of teens, prohibited Web site operators from selling ads that appear to offer a "commercial sex act" with a minor.

The city is expected to respond to Airbnb's motion by July 14. The matter is pending in front of U.S. District Court Judge James Donato.