http://www.slate.com/articles/news_and_politics/jurisprudence/2015/06/city_of_los_angeles_v_patel_the_supreme_court_rules_that_police_can_t_simply.html

In a decision heralded as a big win for privacy rights, the U.S. Supreme Court decided, on 5–4 lines Monday morning, that the Fourth Amendment prevents the city of Los Angeles from enforcing a 116-year-old ordinance that compels hotel operators to turn over certain records to the police. In an opinion authored by Justice Sonia Sotomayor and joined by Justices Ruth Bader Ginsburg, Stephen Breyer, Elena Kagan and Anthony Kennedy, the majority struck down the ordinance punishing hotel operators that refuse to turn over such records “without affording them any opportunity for pre-compliance review.” Justice Antonin Scalia penned a feisty rebuttal in response, accusing the majority of making it vastly more difficult for cops to break up drug rings, human trafficking, and prostitution operations.