An ATCT Local Controller elected to not allow local area law enforcement flight operations in his airspace due to congestion during a peak traffic period. Believes a resulting reprimand from a supervisor was unwarranted.

Narrative

After thunderstorms had postponed our XA:30 push; the weather was finally clearing out. We were technically VFR; but there was a lot of scud; and our windows were fogged; a known issue that is requiring a several thousand dollar contract to fix. Normally; the Sunday XC:00 rush is one of the busiest of the week. Now it was going to include a lot of the XA:30 arrivals as well. Our three finals for XXL/XXR and YY were packed with simultaneous approaches. TRACON called to see if I could let a familiar law enforcement aircraft into the airspace to work northwest of the airport. These flights have a reputation for being very workload intensive. They often have to be called several times and seldom stay in the area they request. I'm not blaming them; it is just the reality of working them. There were approximately 100 departures of which 75+% would be flying through the area requested. I considered the weather; equipment (the window problem); the operational flow; including the fact any go arounds would be climbing right into the area and the problems inherent with managing and communicating with law enforcement aircraft.Our procedures state that we give these flights priority but may refuse service for safety reasons. In accordance with those written procedures I; therefore; refused access to the flight. My Supervisor; who has been at a Center for the last 10 years; wrote up a performance review on me stating I did not use good judgment in my refusal. If a combination of weather; workload; [faulty] equipment; airspace; and controllability of the involved aircraft aren't justifiable safety reasons to prevent a possible loss of separation or collision; what is?I think we should remove the Supervisor's authority to assess a situation like this. Possibly turn it over to a facility panel. We have two Supervisors with no Tower experience and the one mentioned hasn't worked in a Tower in over 15 years; excluding the current one (about a year). I have nearly as much local Tower experience as ALL our first line Supervisors combined. Write-ups like this create unreasonable pressure on experienced controllers to approve activities that they know they shouldn't. Sometimes pilots cannot be allowed to do whatever they want; whenever they want. Sometimes the answer is no.