What is BAC ?

History of BAC Limits and DWI Laws in the United States

For anyone born in the United States after the year 2000, they’ve never lived in a time where the BAC limits in the United States were over .08% in any of the 50 states, and they absolutely wouldn’t remember when the legal drinking age was 18 as opposed to 21.

The history of drunk driving, BAC limits and DWI laws in the United States is long and has increased in strictness by a large margin throughout the last century.

Let’s go back to the turn of the 20th century. In 1910, New York was the first state to pass any law regulating driving while intoxicated, with the state of California following soon after. However, neither of these first laws included any quantifiable level or number that would lead to a conviction, and were more commonly dealt with by means of a fine. A loss of a license or driving privileges during this time where few people could afford to have a personal car was highly uncommon. Other states between the two coasts followed suite and also passed laws addressing drinking and driving, but those laws were also generalized and illdefined.

After the prohibition of alcohol in the 1920’s throughout the United States, it wasn’t until the 1930’s that things started to heat up on the DWI and drunk driving law front.

In 1936 an initial version of the Breathalyzer was invented by Robert F. Borkenstein in collaboration with Indiana University toxicology professor Rolla N. Harger, called the “Drunkometer”. The Drunkometer was a contraption similar to a balloon that people would breathe into and, according to The Washington Post, “took advantage of the fact that alcohol consumed by a person enters the bloodstream, goes through the lungs and is exhaled. The concentration of alcohol in deep lung air is related to the level of alcohol in the blood.”

Soon after the Drunkometer invention, in 1938, both the National Safety Council and the American Medical Association put together a task force that began to research and develop criteria to determine the relation of alcohol and car accidents. Upon the conclusion of their studies, both groups suggested a standard and specific blood alcohol content level of .15% that would inform the max BAC level allowed for drivers who were pulled over for intoxicated driving.

Some 15 years later, Robert F. Borkenstein invented the Breathalyzer in 1958 that we still use today. It uses chemical oxidation and photometry (the science of the measurement of light in terms of its perceived brightness to the human eye) to determine alcohol levels in an individual by measuring alcohol vapors in the breath.

Despite the invention of the Breathalyzer and the research done by the National Safety Council and the American Medical Association, the 1960s were a pretty lax time socially regarding drunk or impaired driving.

During this time laws had harsh penalties and fines, but the likelihood of them actually being applied was slim. The National Highway Traffic Safety Administration worked during this time to show graphic photos of the dangers of drunk driving to sway legislators into tightening the reigns, and some states did lower their allowed blood alcohol content levels to .12% or .10%, but it wasn’t until the 1970’s that the federal and state governments alike really committed to stricter laws.

One of these laws include the switch of the legal drinking age from 18 years of age to 21 years of age, in addition to many states passing “per se” DUI laws beginning in 1972 which made it so the state did not need to prove that alcohol affected the convicted driver’s ability to drive a car, but rather only needed to prove that the driver had a BAC over the limit while operating a vehicle. These per se laws still apply today in all 50

US states, though they now apply to a lower BAC than they did nearly 50 years ago.

In the late 70’s and early 80’s there was a greater push in drunk driving laws after the formation of RID (Remove Intoxicated Drivers) in 1978 that was the first ever anti-drunk driving organization in the US. This organization was followed by the well-known Mothers Against Drunk Driving (MADD) organization that began in 1980 and was pioneered by Candice Lightner and Cindy Lamb who both had children die from accidents related to being hit by drunk drivers.

During this time, DUI laws changed in response nationwide with the legal BAC limit receiving a decrease from .15% to .10% in the 1980s, and Utah being the first state to lower its legal BAC limit to .08%, the limit that is held to be the standard in present day.

The 90’s brought about stricter laws involving drunk driving offense, most notably seen in “Zero Tolerance Laws” that focused on underage drinking and driving, meaning minors who had BAC over “0” would be automatically charged with a DUI, even if they were under the legal limit for adults.

According to the National Highway Traffic Safety Administration, almost one-third of all deaths of minors aged between 15 and 20 years old are related to alcohol.

In 2000, President Bill Clinton signed a bill that required all states to lower their legal blood alcohol content levels to operate a motor vehicle to .08% by a deadline of October 2003, or they would lose all their federal highway construction funds. By October 1st of 2003, it’s reported that 45 of the 50 states had passed laws to lower to legal BAC to .08%, with the remaining 5 states falling in line by July of 2004.

That brings us to present day, where .08% is still the maximum BAC allowed to operate a motor vehicle, and DWI convictions are seriously persecuted and can result in jail time, fines, and loss of license.

According to the U.S. Department of Health & Human Services, “in the mid 1970s, alcohol was a factor in over 60% of traffic fatalities. Traffic crashes were the leading cause of alcohol-related deaths and two-thirds of traffic deaths among persons aged 16 to 20 involved alcohol.”

They go on to say that “Since the early 1980s, alcohol-related traffic deaths per population have been cut in half with the greatest proportional declines among persons 16-20 years old” and, “Today alcohol is involved in 37% of all traffic deaths among persons aged 16 to 20.”

Thank you for visiting the Jarvis, Garcia, & Erskine blog. We write to inform Austin locals about law changes, events and news.