The Security Checkpoint is a building unlocked in the World Wars era that can only be build adjacent to a road in order to set up a roadblock. It employs a single (High School educated) policeman.
It has the following effects:
Decreased Liberty in the area.
Slowing of traffic.
Increased Crime Safety.
Toll Taxes: Generates a small amount of money for your Swiss Bank Account for each vehicle that passes the roadblock.