What are the different tests for intoxication?

Although the law enforcement officer will begin looking for signs of intoxication before they even pull a suspect over, there are certain standardized testing procedures that are instituted in Florida for dealing with suspicions of intoxication.
The first line of testing you will encounter when a law enforcement officer suspects you of intoxication is known as Field Sobriety Testing (FST).  They are performed before arrest, at the venue where the officer initially pulled over the suspect.  These tests are designed to test motor skills, balance and accuracy that are often impaired with alcohol consumption.  Common tests that you may encounter include:

  • Being asked to touch a finger to your nose
  • Being asked to balance on one leg
  • Being asked to walk in a straight line, heel-to-toe

Highly subjective and the subject of scrutiny, these tests are notoriously difficult and, in many cases, are inaccurate metrics of intoxication.  Even under ideal conditions, as many as half of completely sober test-takers cannot perform the tests to the required standards.  When performed in the field, exigent and environmental factors further impact the results of the tests.
The second line of testing you will encounter is a chemical test, typically performed after arrest has been made.  There are three main categories of chemical testing you may find:

  • Breath test (breathalyzer)
  • Blood test
  • Urine test

All of these tests measure the amount of alcohol in the blood stream.  Alternatively known as Blood Alcohol Content (BAC), Blood Alcohol Level (BAL), blood alcohol concentration and others, they usually give the percent of alcohol in the blood stream by volume.

The breathalyzer requires that the suspect blow into a machine for a certain period of time, then indirectly measures the BAC based on the concentration of alcohol in the breath.  The blood and urine tests require the suspect to provide a sample of bodily fluid to be tested either on-site or in a lab.

All of these tests give a fairly accurate measurement of the BAC, and are generally the measurement relied upon by the prosecution and the courts when dealing with a DUI case.

Posted in: DUI