I've been on roads where this happens in Britain, when a police car is driving at the speed limit (generally quite loosely enforced on motorways) with people be

I've been on roads where this happens in Britain, when a police car is driving at the speed limit (generally quite loosely enforced on motorways) with people behind forming a cluster which won't overtake out of fear. Quite frightening, and surely combining the worst of all worlds in terms of accident risk (both a high risk of an accident and a high risk of an accident causing fatal or serious injury). I asked my aunt, who is a police officer, about this, and she said in general the police try and drive slowly (well below the speed limit) on the motorways to prevent this phenomenon from occurring. I wonder whether the guy I saw was doing it deliberately or had just forgotten..