Legal Blog

A DUI conviction can have serious consequences. Hefty fines, jail time, driver’s education classes, supervised probation, license suspension, sky rocketing insurance premiums, and job loss are just some of the possible ramifications of a DUI conviction.

With such high stakes for the hundreds of thousands of people arrested annually for DUI, it’s important for testing methods to be accurate so that an innocent person doesn’t unjustly suffer the consequences of a conviction – but are they?

When a suspected drunk driver is pulled over, a police officer will generally begin by administering a field sobriety test. This involves a number of tasks designed to test the balance, coordination, reaction times and cognitive functioning of a drunk driving suspect.

The accuracy of this testing method is rarely consequential in court today because of scientific methods available and utilized to get a more objective measurement of intoxication. However, in the rare circumstance where a police department or state body loses the results of a scientific DUI test, or is otherwise unable to present them as evidence in a DUI case, testimony about your performance on a field sobriety test could be important.

Reasons Field Sobriety Tests Perform Poorly

In the minority of cases that turn on field sobriety tests, it’s important to know that there are many reasons someone may perform poorly on a field sobriety test that have nothing to do with intoxication. Being distracted, nervous, tired, hungry, dizzy, or in pain are all reasons someone sober may fail a field sobriety test.

Other people just aren’t very coordinated despite having had nothing to drink. For these reasons, field sobriety tests are subjective and unreliable. Police officers and courts know this, which is why, except in special circumstances, more scientific methods are relied on to determine if someone has been drinking, and how much.

There are three common scientific DUI testing methods: blood, breath, and urine testing. Blood samples provide the most accurate reading of intoxication and there is little margin of error with this method. Falsely high readings can occur when a testing laboratory fails to adhere to best practices and standards, and doesn’t sterilize equipment or preserve samples properly. Otherwise, however, blood test results are a reliable indicator of blood alcohol content.

Breath tests are administered via a breathalyzer, which measures how much alcohol is in the air that you exhale. This measurement of alcohol content in the exhaled air is then multiplied by a number which is supposed to represent how blood alcohol and exhaled air alcohol content correlate on average. Not surprisingly, this average is not always an accurate reflection of someone’s blood alcohol content.

Alcohol in the air you exhale doesn’t necessarily mean alcohol in your blood. Throwing up, burping, tooth medication, mouthwash, and even mints can lead to a falsely high breathalyzer reading. Breathalyzer machines must also be routinely re-calibrated, and can give false readings when they aren’t functioning optimally.

Urine tests are less accurate than either other method, and are generally only relied on as a last resort. This method also involves calculating an average based on how alcohol in the urine generally corresponds with alcohol in the blood.

Just as with breathalyzers, however, these averages are not always reliable. The urine in someone’s bladder may have a high alcohol content if they have not emptied it since ingesting alcohol, even if it is no longer in their bloodstream, leading to falsely high readings.

If you need representation for your DUI charge, contact Philadelphia DUI Lawyer Michael Fienman today at (215) 839-9529.