If you get arrested and charged for drunk driving – also known as driving under the influence, or DUI – in Washington or any other state, one of the biggest pieces of evidence that will be used against you will be your blood alcohol content (BAC). In fact, there are cases where a BAC that is above the legal limit will be the only piece of evidence that the prosecutor has to go on.

But what, exactly, is BAC, and how is it computed?

What Is Blood Alcohol Content?

Your blood alcohol content is nothing more than the amount of alcohol that is in your blood. It is given in a percentage, to show the ratio of blood to alcohol. The number of your BAC can show how complex the human body really is: A change of a few hundredths of a percentage point can make a drastic difference in how you feel.

How Does Alcohol Get into Your Blood?

When you swallow a liquid that has alcohol in it, the entire liquid moves into your stomach, and then into your small intestine. As it gets there, it passes through the walls of your organs and into your bloodstream, where it cycles through the rest of your body, including your brain, which is where it has the most impact.

Importantly, your blood absorbs alcohol at a set, known rate. Because of this, the amount of alcohol in your blood is a good indication of how much alcohol there is inside your stomach, which shows how much you have been drinking recently.

How Does Your BAC Get Measured?

The science behind BAC makes it seem like a perfect indicator of your level of intoxication. However, even if the number of your BAC percentage was a direct correlation to how drunk you are – which it is not – the practical aspect of accurately measuring the blood inside your body for its alcohol content is far from perfect.

Because it would be unreasonable to expect police to perform blood draws during a traffic stop, law enforcement uses breath tests instead. The amount of alcohol in your breath is supposed to exactly replicate the amount of alcohol in your blood. However, there are a whole lot of complications that can arise and make the percentage of alcohol in your breath much higher than what it is in your blood – so many that it would take a whole new blog article to even list them all.

Call a DUI Attorney

While the theory of BAC is solid, the practical reality of testing you for your BAC is far from scientific, and fraught with uncertainties that can raise your BAC reading and take you over the legal limit. Having a DUI attorney on your side who knows this, and who understands how to argue this to a jury, can mean the difference between an acquittal and a costly conviction.

Call the law office of Steve Karimi at (206) 621-8777 or contact him online.