I can’t think of any reason why a police officer in Kenya should get a free ride in a matatu (minibus use for public transport). As far as I know there’s no law that says, “If you see a cop walking, give him a ride.” It happens all the time, though: some cop walking on the side of the road flags down a matatu and the guy jumps in. For some reason every non-Kenyan person I complain to has the gut reaction to tell me that its because cops “serve the public.” Um, hello? Which Kenya do you live in?