Mounting a DUI Defense: Chemical Tests Taken During the Absorption Phase

If you are pulled over and given a chemical sobriety test, results may depend on the current absorption phase. In some circumstances, test results could be inaccurate, and you may receive a DUI even though you weren’t intoxicated at the time.

Understanding How the Body Absorbs Alcohol

To understand how chemical tests during the absorption phase may be inaccurate, you’ll need a clear picture of how alcohol is absorbed by the body: 

  • absorption – when a person begins drinking, the body starts to absorb alcohol immediately. Absorption happens so quickly that the body cannot eliminate it as fast as it is consumed. This is why blood alcohol content (BAC) steadily rises when someone is drinking; the alcohol is coming into the body faster than it’s going out.
  • continued absorption – when a person stops drinking, the alcohol that has already been consumed continues to be absorbed. This means that a person’s BAC will continue to rise for a time even after they’ve stopped drinking.
  • peak – after all the alcohol has entered the blood stream, the person’s BAC is in balance, meaning the absorption and elimination are occurring at exactly the same rate. The BAC will flatten out and remain the same during this window.
  • elimination – the last phase is elimination, in which the BAC slowly drops because the elimination is greater than the absorption. Just how fast the BAC levels drop depend upon a number of factors including, gender, body weight, and the person’s food intake.

Inaccuracies of Chemical Testing

Breath tests have a few inherent inaccuracies. “Research indicates that breath tests vary at least 15 percent from actual blood alcohol concentration. At least 23 percent (that’s about one out of every four) of all individuals tested will have a BAC reading higher than their actual BAC,” reports Dr. David Hanson (SUNY). If the machine isn’t properly calibrated or the test is administered incorrectly, defendants may challenge the results of the test.

Further, urine testing may produce inaccurate results because much depends on when the driver consumed alcohol and last voided his or her bladder. If alcohol was consumed several hours prior but the driver had not emptied his or her bladder, it could produce BAC results higher than the true BAC.

Challenging the Accuracy of DUI Chemical Tests

Chemical tests administered during the absorption phase may produce inaccurate results. Therefore, a defense can be built around possible inaccuracies in a particular case in order to combat DUI charges.

It’s important to build a defense against unfair DUI charges, because a conviction can mean harsh penalties such as: 

  • driver’s license revocation for a six-month minimum;
  • large fines up to $1,000;
  • probation for up to a year;
  • 50 hours of mandatory community service;
  • jail time up to nine months; and
  • vehicle impoundment. 

Penalties may be higher on subsequent arrests. For legal questions regarding DUI charges, or for help mounting a defense and fighting charges that have been brought against you based on chemical sobriety testing, consult a DUI defense lawyer.