That new law, the California Electronic Communications Privacy Act (CalECPA), requires law enforcement to obtain a warrant before searching a person's cellphone, laptop, or any digital storage device. At issue is whether the law covers people on probation, parole, and other forms of supervised release who've agreed to what's known as a "Fourth waiver," a condition that allows law enforcement to search their person and property at any time.

CalECPA took effect on January 1, 2016. Three days later, San Diego County prosecutors and Superior Court judges began asking defendants who were eligible for probation to sign a form giving "specific consent" to county probation officers "and/or a law enforcement government entity" to collect information that would be otherwise protected under CalECPA.

The consent form described everything that could be searched and seized: