Blood and Breath Tests

Many people who submit to a chemical test (blood or breath) and register above the legal limit (.08% blood alcohol for DUI and .02% blood alcohol for Underage DWI), often mistakenly believe that their case cannot be successfully defended and thus choose not to retain a lawyer. However, an investigation of the case by a Tennessee DUI attorney often reveals evidence that calls into doubt the reliability of the chemical test and may even result in keeping the test results from being introduced in court (suppression of the evidence).

The Tennessee DUI defense lawyer you hire should be familiar with the many factors that can affect the result of a chemical test (blood test or breath test). Such factors often lead to an incorrectly reported high blood alcohol concentration. Depending on the type of specimen and analysis, the following are some of the factors that should be investigated to ensure the reported chemical test was accurate:

  • Radio Frequency Interference (which may be caused, for example, by a police radio, a microwave, or a cellular telephone)
  • Mouth Alcohol During Collection of a Breath Sample
  • Foreign Substances in the Mouth (for example, tongue stud or dentures)
  • Gastroesophageal Reflux Disease (GERD)
  • Observation of the Subject Prior to Administration of the Test (State v. Korsakov is a Tennessee DUI case that discusses this issue)
  • Diabetes
  • Method of Blood Extraction
  • Blood Sample Storage
  • Preservation of the Blood Sample
  • Transportation of the Blood Sample
  • Blood or Breath Sample Analysis
  • Proper Elimination of the Breath Sample from the Body

While this subject matter is too lengthy to properly discuss on a web page, our lawyers have written and lectured extensively on this topic. See, for instance, Mr. Oberman’s two legal texts–Drunk Driving Defense and DUI: The Crimes & Consequences in Tennessee.

Featured Posts

bail for a felony
June 11, 2024

Bail for a Felony Criminal Offense Just Became More Restrictive

Being arrested for any criminal offense is never a positive experience.  In Tennessee, two main genres of criminal offenses exist.  The first, is a Misdemeanor offense.  These offenses are typically considered less serious offenses (with some serious exceptions, of course).  […]

Read More
underage drinking
May 11, 2024

Underage Consumption of Alcohol in Tennessee is more of a headache than you think.

As most folks should know, if you are under the age of 21 you are not allowed to consume alcohol in Tennessee (and all other states in the U.S.).  In fact, an underage person who has been drinking or is […]

Read More
April 12, 2024

New DUI Law Alert–Work Release Requirement Update

The Tennessee Legislature passed several new laws that became effective on January 1, 2024.  One DUI related law involves the Tennessee Work Release Program.  Work release is a form of probation that may be used, in certain circumstances, after a person has […]

Read More



Oberman & Rice
550 Main Street
Suite 730
Knoxville, TN 37902

Phone Number
(865) 249-7200
(865) 540-1696 (fax)

GPS Coordinates
Long: 35.970504
Lat: -83.914776

contact us today for a free consultation

We reply to non-urgent after-hours requests for consultation within 24 hours. For after-hour emergencies, please call us at (865) 249-7200.

Fields marked with an * are required