What is “Rising Blood Alcohol Concentration”?

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In Ohio it is illegal to drive a vehicle with a blood alcohol concentration (BAC) of .08 or greater.  However, a driver’s BAC is not measured at the time that they are stopped by the police.  Usually, the driver’s BAC is not measured until one, two, or even three hours after they are first stopped and taken to the police station.

This is a problem because the person’s body is constantly either eliminating or absorbing alcohol.  If the person’s body is still eliminating alcohol then their BAC is falling and will therefore be lower than it was when they were driving.  If the person’s body is still absorbing alcohol then their BAC is rising and will be higher than it was at the time they were driving.  It is this “rising” BAC that creates an unfair situation.

Consider someone who has a couple of shots of whiskey right before they leave a bar.  The person only has a few blocks to go, but unfortunately, they’re stopped before they get home.  The officer smells alcohol, the driver doesn’t fare so well on the field sobriety tests, and they are taken to the police station for a breath test.

By the time they get to blow into the breath test machine, that whiskey has been absorbed into their blood and is significantly higher an hour after they were driving than what it actually was when they were driving and only minutes from home.

Scientists have uniformly rejected attempts to estimate a person’s BAC at the time the person was driving based on what their BAC is at the time they were tested.  This is due to the fact that each person’s body absorbs and eliminates alcohol at different rates.

Legislatures have skirted the problem of attempting to determine what the person’s BAC was at the time they were actually driving by passing laws that create a presumption that if the person’s BAC is .08 or higher within a certain time after they were stopped, then it is presumed to be at that same level at the time they were driving.

These laws effectively shift the burden of proof to the defendant to show that their BAC was lower at the time they were driving than at the time they were tested, and creates a presumption of guilt.

If you have been charged in Columbus with OVI and took a breath alcohol test, contact an experienced Columbus DUI Attorney.