My "no" was simply because there are already enough legal structures in place for this. If there is a reasonable AND JUSTIFIED suspicion that the driver had been texting they should normally not have any problem getting a warrant signed by a judge asking for the relevant meta data. No new techniques needed that can be abused for other purposes.
In addition, I support the notion that a responding policeman is unlikely to be able to do this correctly, even trained. I've seen in the UK what so-called "trained" policemen are capable of and I'm sorry, but as far as I can tell the training was a pointless exercise, also because they don't seem to have the faintest clue how to interpret the data they so gather which makes MISinterpretation not just possible, but likely and it's a sure bet that is never going to be in your favour.
After all, they don't need innocents. Their statistics need convictions.