As of 2004, all 50 states have established an "illegal per se" BAC of .08 for the offense of DWI. Delaware, being the last and final state to pass the .08 BAC law, previously had in place a .1 BAC statute.
In 2000, Congress and President Clinton signed a law requiring all states to enact a .08 BAC statute by 2003 without losing a percent of highway funding. Before this, only 19 states had passed per se .08 BAC laws.
A person's BAC is normally expressed as the percentage of alcohol in the blood. Generally, a person weighing 160 lbs would reach a BAC of .08 with four drinks. Along with simply ingesting alcoholic beverages, the lapse of time and the way your body metabolizes the alcohol will all play a specific role in the creation of your unique BAC.
With the thousands of convictions here in the United States every year for DWI, you would think that our BAC illegal per se limit of .08 is unreasonably low. But, when comparing a limit of .08 to the rest of the world, the 50 states seems to be quite forgiving with their drinking and driving statutes.
For example, roughly 70% of the countries around the world with applicable statutes have BAC illegal per se limits as .05 or lower. Sweden, specifically, has a BAC limit of .02. For the same person weighing 160 lbs, just one drink could put them over a BAC of .02.
Thousands of Americans are charged and convicted of driving while intoxicated. This being said, many of those individuals were shown to have a BAC level of over .08 when operating a motor vehicle. Our 50 states, as opposed to most of the world, have decided that we are capable of driving safely despite having a limited amount of alcohol in our system. But, it is up to us to abide by those laws and keep our streets safe.