So I voted on your model and came back to see the results:
Paintjob Rating: 1.75
Coolness Rating: 2.25
I suspect, much like my Ultramarines who were downvoted simply because they were Ultramarines, I imagine your model got lower votes simply because it is endorsing the police. (Which is sad, why down vote something because of that? The model looks good, why down vote it because it is an Ultramarine, or related to law enforcement etc :( )
Personally, I gave you a good vote according to how unique this is and the overall paint job (which I liked both the paint job and the concept).
I added tags for you as well.