can i say,
(a)He has been / was taken to the police
station.

Both correct, but:

(a)He has been taken to the police
station. (BrE usage)

(b)He was taken to the police
station. (AmE usage)

Both sentences can be used in the US or the UK, Vincent.

Here's one typical use of the present perfect (has been taken) that the simple past (was taken) doesn't have: The present perfect can be used to show that something happened very recently, perhaps so recently that it is still influencing or affecting the present.

The simple past tells us something happened in the past, but we have no clue if that was yesterday, last week, or ten years ago unless there's more context in the sentence. With the present perfect, we don't have that doubt.

Here's another example. "I've done it!" (perhaps only a few moments ago). "I did it!" (I'm not sure when, only that it was in the past.)

Richard