At the very start of the game (the first time you have control over the character), you must very slowly walk through the first two doors. Do not run. Walk as slowly as possible to get the "Law-Abiding Citizen" achievement. This can be your first trophy in the game. If you already completed this mission, you can replay it through mission select at any time (under the pause screen where you view the map and upgrade your character etc.). You can abort the mission after getting the achievement.