Police XP, or Cop XP, is one of three levelling systems implemented in Sleeping Dogs.
Police XP shows Wei's achievements and developments during his undercover stint. Like the Triad Meter, the Police Meter affects the XP you gain during missions and the four Police Cases. Avoiding misdemeanors, such as theft, harming civillians and property damage, during the missions and Police Cases will allow you to fill the XP meter. The Police Meter cannot be filled, so avoiding these misdemeanors is pivotal for the best outcome. Busting up drug deals will also earn you Police XP by default.
Beginning at Level 1, you are simply given access to the cell phone by default. Like the Triad XP levelling system, the rewards then branch out into two paths - one branch allowing you to improve your shooting skills, and the other improving the use of vehicles in the game. The mechanics of it are exactly the same as Triad XP - the purchasing, access and use of the Upgrades are practically identical.
It is recommended that you primarily focus on the branch involving guns and shooting for later missions and side-content in the game, before focusing on the vehicular branch. This should allow you to tone down some of the difficulty of the later missions, counting that you are a good shot.
Police XP has some brilliant perks to its rewards, and it is advised that you work on this when the storyline begins to heat up.
