One point which I haven't seen come up in any discussion of this: Michigan now prohibits texting while driving. So at least in theory, checking your cell phone

One point which I haven't seen come up in any discussion of this: Michigan now prohibits texting while driving. So at least in theory, checking your cell phone could determine whether or not you were violating this. I wouldn't be surprised if that is a major part of the justification for this. Of course, even that wouldn't justify anything but getting your last few minutes of chat log off the phone...