The mass production of automobiles at the turn of the last century changed life in the United States drastically. There was a sudden need for gas stations, better roads, motels, and of course... laws regulating traffic, driver education/safety and the construction of the automobile itself.
We recently added a report to the State Library of Kansas' KGI Online Library prepared by the Kansas Legislative Council's Research Department in 1936, "Safety Regulation for Motor Vehicles." It was one of two major reports issued by the Legislative Research Department to assist members of the Kansas State Legislature in writing good laws regulating motor vehicle use in the state. The report touches on traffic signals/signs, drivers' licenses, brakes, headlights, speed limits, etc etc etc. The need for improving Kansas vehicle related laws and regulations was definitely pressing.
You can view this publication here: