As the year draws to a close, EFF is looking back at the major trends influencing digital rights in 2011 and discussing where we are in the fight for a free expression, innovation, fair use, and privacy.

2011 saw 40% of all mobile phone users in the United States carrying web-enabled smartphones, creating a cycle that results in cheaper smartphones and more first-time users. People who carry smartphones are usually carrying all of their sensitive information with them too. Today, phones do more than just store contacts and dial phone numbers. Now, people are carrying years of email correspondence, text and instant messages, bank and financial records, personal photos, calendars, websites they've visited, places they've visited, even the books they read. So, with all the mobile computing smartphones are capable of, it comes as no surprise that law enforcement wants to get their hands on the digital goodies. And unfortunately, in 2011 courts gave them the ammunition to do so.

The Fourth Amendment's prohibition against warrantless searches and seizures applies to cell phones, and EFF has long advocated for the police to come back with a warrant before searching a cell phone. But in January 2011, the California Supreme Court ruled in People v. Diaz (PDF), that the police were authorized to search any person's cell phone, without a warrant, after they had been arrested under the narrow "search incident to arrest" exception to the Fourth Amendment, that permits a brief search in the area immediately around a person for the purposes of officer safety and protection of evidence from immediate destruction. 

We predicted Diaz would create routine privacy violations, and worried that officers could use a pretextual arrest to casually browse the data on a person's cell phone for any reason, even if that person is never charged with a crime. We weren't the only ones worried. In April, California Senator Mark Leno introduced a bill intending to revserse Diaz and require the police to obtain a warrant before searching a cell phone incident to arrest. Sponsored by the ACLU of Northern California, and supported by an EFF Action Alert, the bill passed through both houses of the California legislature before being vetoed by Governor Jerry Brown. As Governor Brown explained it (PDF), "Courts are better suited to resolve the complex and case specific issues relating to constitutional search-and-seizure protections." Yet, courts across the country have been struggling to deal with this issue. The Ohio Supreme Court, interpreting the same "constitutional search-and-seizure" protections as the California Supreme Court in Diaz, reached the opposite conclusion, prohibiting warrantless cell phone searches. Faced with this conflict of opinion, the United States Supreme Court, a week before Governor Brown's veto message, declined to review the Diaz opinion. 

So with conflicting court opinions and the legislative fix in California struck down by a Governor who bowed to the pressure of law enforcement, is there any good news?

Well, rest assured that EFF is committed to helping you protect the private information on your phone. This summer, we published a "Know Your Rights" guide (and quiz!) designed to help you understand your rights when an officer's prying hands start reaching for your cell phone. And in the wake of Occupy Wall Street and their use of cell phones for coordinating protests and documenting abusive law enforcement techniques, we published a guide on how you can protect your cell phone before you occupy (or do anything else for that matter). Even mobile phone app makers are getting in on the act, with apps like "I'm Getting Arrested" for Android devices making appearances at Occupy rallies. And in 2012, we're going to be keeping an eye on warrantless cell phone searches, so that when new threats to cell phone privacy emerge, EFF will be sure to pick up the call.