Vauxhall Insignias are the worst driven cars on the road, technically though it's still a German car. Nissan appear to be the worst single make, they cover all bases from dawdlers (Micra/Note) to the aggressive (Navara pickup).
Why do our traffic patrols drive BMW's? Do the Bremahavern Moteur Vorken or what ever their crap name is give a massive discount to buy their rubbish. Cynic Cynic!!!!!
I notice government cars are BMW as well. Even a common Ford would be a bit? more patriotic at least some of it is made in Blighty.
I going to make an educated guess that it's down to residuals and a flexible factory ordering system, allowing the Police to specify a suitably large enough estate body with a big six cylinder diesel, sporty suspension and base spec. That and the large mainstream car has all but been killed off so alternatives are thin on the ground.
There was brief love affair with Volvos back in the late 90s/early 2000s after the switch towards estate cars, that appeared to snuff out though. Lots of stories of the Police stockpiling Rover SD1 V8s in the mid 80s and Vauxhall Senator 24vs a decade later after production ended. Vauxhall Omega never achieved the same status (and still 'German'), the Rover 75 estate was probably too little too late.
BMW have an engine plant here in the UK like Ford, not sure what engines are made here.