DUI Information: Questioning the Reliability of Breathalyzer Tests

Breath analysis is probably the most commonly used technique by law enforcement in attempting to establish whether or not a suspect was driving with alcohol in the system beyond a legal limit. However, the reliability of the breathalyzer test has been called into question.

Each state has enacted an implied-consent law. These laws provide that every licensed driver within the state is considered to have given his or her consent to chemical testing to determine his or blood alcohol content (BAC) whenever a law enforcement officer has reasonable suspicion of intoxication. Refusal to submit to such a test can result in a license suspension or revocation in most states. A blood test is more reliable in obtaining the BAC, but the breath test is used in the field due to its transportation convenience and its ease of administration. This test can be used by non-medical personnel, is less physically intrusive, and provides faster results.

The breathalyzer test was invented in 1954 to collect evidence of intoxication by measuring BAC through breath analysis. Since that time, several manufacturers have stepped in and the science behind the machine has evolved. However, breathalyzer tests, as they are currently administered by law enforcement officials, are considered by some experts to be inaccurate as far as their ability to measure blood alcohol content. In some cases courts have thrown out breath test results because of their unreliability.

For example, thermometers are used in the breath-test machine. Operators test the machines by getting a reading from an alcohol and water mixture. This mixture must be kept at 34 degrees centigrade. In one case in 2002 in Washington Supreme Court an alcohol breath test was thrown out due to the thermometers. The Supreme Court in that case ruled that evidence wasn't produced to show that the thermometer on the machine used to give the woman a breath test had been certified as reliable. Another court has even reversed DUI convictions on the grounds that breath tests are unreliable. In New Jersey they considered the appeals of four defendants whose convictions involved breathalyzer tests.



If you are accused of drunk driving, experienced criminal defense lawyers can help. Individuals facing felony or misdemeanor charges should seek legal representation as soon as possible.