Thanks all round for the feedback, guys!
Interesting thoughts and examples from all sides. As a professional translator I am pretty much familiar with the conceptual variations and grammar of the noun (group) discussed here, but your answers and thoughts are still very nice to hear. As regards my original question
your responses confirm my impression that in "standard, educated" American English one would
normally say, for example, "The police are hunting the criminal" or "The police are coming!" and not "The police is hunting the criminal" or "The police is coming!". Surely one can find exceptions in usage, some dependent on a particular context or possibly more 'streetspeak' but my concern here was to understand on which side the scales usually tip in the US. Above all, none of you AE guys has jumped in to say
No, we say things like 'the police is on the way here' all the time. So that seems pretty clear. -- If anyone
does want to contradict this finding, then please shoot...!!
In British English we tend to treat collective nouns as a plural anyway. But since I currently need to translate a lot of spoken German into AE and "die Polizei" occurs quite frequently, this was my main point of focus. Now I can enter into discussion with my client again on a sounder footing.