As with all the civs the Police will be rated on a 5 star basis in 4 categories.

Difficulty: |
Fun: |
Cost: |
Time: |

Here's how the ratings work. Difficulty is how hard it is to play a certain civilization; one star would denote that it is simple while five stars would denote it being very hard to win. Fun is the amount of enjoyment you can extract from playing as a certain civilization; one star means that it is boring or impossible while five stars indicates that you could extract much joy from it. The Cost rating is the average cost of units and how expensive it is to build them; one star being cheap deathtraps while five stars denoting expensive and destructive units. Time indicates the average ammount of time it will take to win as that civilization; while one star represents a quick finish, five stars indicates that an end could take a very long time.
My thoughts: While the allure of playing as the police is possible very attractive, playing the police can be downright boring. The police have superior units and training and often win many of the battles. The police have a huge area of control in the beginning and can produce many of their high power units quickly. If the gangs should get their act together or team up with technology, the police could find themselves in hot water, but I have not seen this yet as playing the police. This scenario could be interesting in a Multiplayer situation though with a player as the police and other players as the gangs trying to fight the power, or as 4 players fighting an AI power. But otherwise, the police are rather uninteresting aside from their multitude of units.