"Het is de taak van de politie om misdaad te voorkomen."
Translation:It is the police's job to prevent crime.
I would say "of the police" instead of "police's", I'm not a native English speaker though.
I am and I agree. I don't know the official linguistics term for this, but "the police" is some sort of non-specific noun which cannot take a possessive apostrophe-S.