If you're up to no good in California, or even if you're just concerned about your personal privacy, a recent Supreme Court ruling may be of interest to you. In the case, People v. Diaz, 165 Cal. App. 4th 732, the Court ruled that the police could search the cell phone of the accused without a warrant. While authorities have always been able to check an accused's clothing and personal possessions for the presence of weapons or contraband, this decision takes that search to a new level. For many people, the contacts, documents, text messages, and other data held in their smart phone makes it more like a briefcase than just an instrument to make phone calls on.
The Court's decision was not unanimous, and there has been a great uproar in the legal community about how this authority to search these devices squares with Fourth Amendment protections. The decision is expected to be appealed to the US Supreme court. In the meantime, if you're worried about the data in your phone, you might want to make sure you've password protected your information.