 African-American travelers faced real physical risks because of the widely differing rules of segregation that existed from place to place, and the possibility of extrajudicial violence against them. Activities that were accepted in one place could provoke violence a few miles down the road. Transgressing formal or unwritten racial codes, even inadvertently, could put travelers in considerable danger. Even driving etiquette was affected by racism; in the Mississippi Delta region, local custom prohibited blacks from overtaking whites, to prevent their raising dust from the unpaved roads to cover white-owned cars. A pattern emerged of whites purposefully damaging black-owned cars to put their owners "in their place". Stopping anywhere that was not known to be safe, even to allow children in a car to relieve themselves, presented a risk; Milloy noted that his parents would urge him and his brother to control their need to use a bathroom until they could find a safe place to stop, as "those backroads were simply too dangerous for parents to stop to let their little black children pee".
