You may be surprised to know that drinking and driving hasn't always been illegal. Surprisingly, some states even allow open containers in vehicles today (Mississippi is a good example).
You know that driving after drinking is dangerous, which is why it's banned by today's laws. However, the first drinking-and-driving laws weren't established until 1910. It was then that the mass production of automobiles started, so the concern of drunk drivers was then becoming more serious than in the past.
Even more interesting was that there was no legal limit established in the past. It was up to the police officers to decide if someone was too intoxicated to drive. It wasn't until the 1950s that the first formal Breathalyzer test was created and used by a police captain named Robert Borkenstein. At the time, the legal limit was .15 percent, based on data from 1938.
In 1998, the federal government took steps to ask the states to reduce the limit to .08 percent. In 2000, the federal government set the legal limit to .08 percent.
What's surprising is that states are still changing DUI laws today. For instance, did you know that Utah's legal limit is .05 percent, the strictest in the country? Every state has the right to establish its own legal limit independent of the federal limit, which is something to keep in mind if you drive for travel.
The BAC limit is still .08 percent in Pennsylvania today. If you're caught with a BAC above this limit, it's a good idea to look into a defense for your case.