The first law against drunk driving was passed in New York in 1910. Before long, every state in the US had outlawed driving a car while intoxicated, which is arguably more dangerous than horseback riding in the same state. These early laws did not specify a maximum BAC (blood alcohol concentration) or describe the tests that must be administered to a person charged with drunk driving. They simply declared that one should not drive drunk and left it up to police officers and judges to enforce this as they saw fit.
The first maximum BAC for the driver was established in 1938: that year, it became illegal to drive with a BAC greater than .15 or 15%. This number was based on studies by the American Medical Association and the National Safety Council, who agreed that research showed that a person with a BAC below .15 could still drive reasonably well.
This remained the law in most of the US until the 1970s. At this time, activist groups such as Mothers Against Drunk Driving (MADD) began campaigning for stricter DWI laws and more vigilant enforcement. Before this time, DWI was not considered a very serious crime and police officers did not always enforce it very strictly. MADD (and its student group, SADD) felt that too many preventable deaths were the result of this lax attitude toward drunk driving. They successfully pressured most states to lower their maximum BAC to .10. Now, due to the influence of the federal government, all states have a maximum BAC of .08.
Other important changes in the law followed. MADD’s involvement was one of the contributing factors in Congress’s decision to raise the minimum drinking age to 21. Of course, MADD wasn’t the only group to pay attention to this issue. From the 1970s to now, people have become more concerned with and less tolerant of DWI crimes. Sobriety checks have become acceptable, when at one point they were considered unfair or even unconstitutional. For drivers under 21, the BAC has been lowered to .01, because legally they shouldn’t drink at all (although in some states, like Texas, minors can drink in the presence of a legal guardian). )
A current controversy in DWI law is the question of what role law enforcement should play in addressing this problem. If a person is convicted of driving under the influence of drugs or alcohol, should he be punished or rehabilitated? Is the punishment approach failing to address the problem effectively, or is the rehabilitation approach simply letting people get away with it too easily?
