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Results from Breath Tests in DUI Cases are Sometimes Inaccurate

No two people are exactly alike, so why do breath tests assume that the drivers being tested for blood alcohol content all have average physiological attributes?  Blood alcohol content (BAC) is one of the main pieces of evidence used by the prosecution and it has to be proven that the driver had a BAC greater than the state’s legal limit.  Too often people are convicted of drunk driving, when in actuality, their BAC was below the limit. 

Breath testing equipment uses a ratio when converting alcohol in the breath to alcohol in the blood.  This ratio can vary from person to person and does not always reflect the driver’s intoxication level.  Unfortunately, when it comes to DUI and DWI, if the results are even slightly off, it could make the difference of whether or not the driver will be accused of drunk driving. Breath tests do not always provide accurate results, as there are many factors that can skew the reading.  Below are some factors that can cause a breath test to give a false reading, which could result in a DUI or DWI arrest.

Radio Frequency
Believe it or not, radio frequency can skew the results of a breath test.  Studies have shown that breath testing equipment can become unstable when located near another device emitting radio waves.  For example, a police officer’s radio can affect the reading of the breath test.

Mouth Alcohol
A breath test analyzes a breath sample to determine how much alcohol is present in the breath.  These machines do not have the capability to differentiate between alcohol in the mouth versus alcohol in the lungs.  There is a huge difference, especially since certain items in the mouth may contain alcohol.  For example, if the driver has dentures, the denture adhesives could leave residual alcohol in the mouth.  So, the reading from the breath test could be off and not accurately reflect the true BAC of the driver.

Other Compounds Mistaken as Alcohol
Breath testing equipment is supposed to identify a particular type of alcohol known as ethanol, which is found in alcoholic beverages.  Sometimes other chemicals are mistaken for ethanol, which can give a higher reading.  There are some compounds that occur naturally in the human body can be mistaken for ethanol.  Also, if certain chemicals are inhaled, such as those associated with construction, the breath testing instrument may interpret these chemicals to be ethanol.

Medical Conditions
Certain medical conditions can affect the breath test results.  According to the National Highway Traffic Safety Administration (NHTSA), dieters and diabetics may have high levels of acetone, much greater than those in other people.  Acetone is a substance that is falsely identified as ethanol.  Therefore, a diabetic could give a higher BAC reading with a breath test than someone who does not suffer from the condition.

If you have been accused of DUI or DWI, you need to contact an attorney immediately who can help you build your defense.  Call (888) DWI-ANSWER (394-2679) or (888) DUI-ANSWER (384-2679) today for legal advice from an experienced DUI or DWI attorney.