There are several minor differences:
The CZ 75 BD police has
1) Loaded chamber indicator
2) Lanyard loop
3) Serrations on the front and back of the grip
4) Extended magazine release
5) And of course, it says "Police" on the slide
6) I have read that it has serrations on the trigger face and that the magazine release is reversible, but I can't confirm these features.
As far as I know, those are the only differences.