De or het rookpolitie?

The correct Dutch article is:

de rookpolitie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use rookpolitie

the rookpolitiede rookpolitie
this rookpolitiedeze rookpolitie
that rookpolitiedie rookpolitie
our rookpolitieonze rookpolitie
your rookpolitiejouw rookpolitie
every rookpolitieelke rookpolitie
which rookpolitie?welke rookpolitie?
a big rookpolitie / the big rookpolitieeen grote rookpolitie, de grote rookpolitie