History of drunk driving laws

The first jurisdiction in the United States of America to adopt laws against drunk driving was New York in 1910, with California and others following. Early laws simply prohibited driving while intoxicated, with no specific definition of what level of inebriation qualified. The first generally-accepted legal limit for blood alcohol concentration (BAC) was 0.15 (in 1938, the American Medical Association created a "Committee to Study Problems of Motor Vehicle Accidents"; at the same time, the National Safety Council set up a "Committee on Tests for Intoxication".
In the US, most of the laws and penalties were greatly enhanced starting in the late 1970s, and through the 1990s, largely due to pressure from groups like Mothers Against Drunk Driving (MADD) and Students AgainstDriving Drunk (SADD) and leaders like Candy Lightner. Most significantly, zero tolerance laws were enacted which criminalized driving a vehicle with 0.01 or 0.02 BAC for drivers under 21.