Already in use. Mobile versions are already deployable as part of the anti-terrorism drive: registration scan, satellite uplinks to a national database of wanted vehicles. Very clever stuff, proven to work as well. Main system is owned by the Welsh forces, but they loan it out occasionally...
Amazing. I didn't realise that grown ups still called the police "pigs". I stopped that when I was about 12, sounded too much like hippy-talk. Always makes me think of Neil from the Young Ones.???