Here you go  

City of Mesa salaries are public, so here's where to find it, and the answer to your question:

https://apps.mesaaz.gov/jobdescriptions/documents/PayPlans/AlphabeticalListing.pdf

Civilian Police Helicopter Pilot: $79,159.60 - 88,572.85

From what I understand they hired their first civilian pilot in quite some time either late last year or early this year as a kind of pilot program to see how it went. Seems like it's working out pretty well, but just an FYI you'll be coming in as an outsider, and likely taking away a TFO's chance at getting into flight school. I'm not saying this to discourage you, just give you a small insight to how you may be seen if you decide to go that route. Seems like there's some great people on the aviation side of Mesa PD though. I think they're in the process of converting thier last 500E's into 530F's, but I'm not an MD guy so I don't know all the details.