I decided from the start to make the player pawns into police cars. That seemed pretty logical, to fit the theme as players travelled around the board. But that wasn’t enough, since it did not go well with the crime investigator stereotype from the 80’s TV series/movies, where the detectives usually drove around in discreet, unmarked civilian cars (often brown, for some reason).
Therefore I decided to make both type of cars available to the player. By simply flipping the car token, players could now switch between unmarked cars and marked patrol cars (with lights and police logo). This way, players could pick the type of car which fitted their chosen type of police character.
Of course, this would not make any sense if the car chosen to drive in did not affect game play. It would be like switching between a fighter jet and a bomber, but have the same weapons load-out, etc., on both!
I toyed around with different ideas about which bonuses to apply to each car. One of the ideas was to have some player cards to be playable only when driving one type of car. However, it seemed too restrictive, and testers often did not want drawn cards to dictate what cars to drive. The good thing about the idea was that players would not be able to immediately spot what car types were best to choose for other players at any given time (including the choice made by the Corrupt Cop).
However, it was not an intuitive way to choose the type of car to drive, and cards drawn initially might not even give you a preferred car to drive, from game start.
Based on this feedback, I ended up giving fixed investigation bonus when driving an unmarked car (thus behaving in a more discreet manner), and a fixed movement bonus when driving a marked patrol car (thus being very visible and recognizable on the streets).
Of course, special circumstances unknown to the player from the start might be affected from the choice of car, and thus the choice of behavior style…