Under the first-of-its-kind legislation proposed in New York, drivers involved in accidents would have to submit their phone to roadside testing from a textalyzer to determine whether the driver was using a mobile phone ahead of a crash. In a bid to get around the Fourth Amendment right to privacy, the textalyzer allegedly would keep conversations, contacts, numbers, photos, and application data private. It will solely say whether the phone was in use prior to a motor-vehicle mishap. Further analysis, which might require a warrant, could be necessary to determine whether such usage was via hands-free dashboard technology and to confirm the original finding.
via http://arstechnica.com/tech-policy/2016/04/first-came-the-breathalyzer-now-meet-the-roadside-police-textalyzer/