Challenging a Breathalyzer Test

Successfully challenging a DUI can result in dismissal (expungement) or a reduced charge such as reckless driving.

Challenging a Breathalyzer Test in South Carolina

For South Carolina, “a breathalyzer” actually refers to a DataMaster unit, which measures blood alcohol via infrared wave readings of breath samples. These units are maintained by SLED at approved breath testing sites across South Carolina. The accuracy of a DataMaster breathalyzer depends on the unit, the timing of the testing and the testing process for the suspected motorist. Plus, there are procedural steps such as videotaping a breathalyzer test, which if omitted, can weaken the prosecutor’s ability to use it as evidence.

Breathalyzer Testing in South Carolina MUST Include…

  • The machine must be properly maintained and in working order.
  • The testing operator must comply with a 20-minute observation period before testing. This 20-minute period should be recorded on videotape. The purpose of  this procedure is to rule out a false reading. If the suspected motorist had a drink just prior to testing, the reading will not be reliable.
  • The collection of breath sample must be taken within two hours of arrest.
  • The test administrator is required to be trained and certified by the South Carolina Criminal Justice Academy.
  • The suspected motorist must be informed of a right to refuse a breathalyzer
  • Before a breath test is administered, a simulator test must be performed on the DataMaster with a result between 0.076 percent and 0.084 percent.
  • Maintenance records on the specific DataMaster must be made available by SLED upon request.
  • The motorist being tested must be notified in writing that he or she has the right to select a qualified person of choice to conduct additional tests. The arresting officer must provide “affirmative assistance” for this endeavor or else any police administered breath test will become inadmissible.

Failure of the legal requirements listed above makes the case to challenge an existing breathalyzer test or procedure. SC ST SEC 56-5-2930, -2950

Challenging a Field Sobriety Test in South Carolina

Field sobriety tests (FSTs) are notoriously bad indicators of intoxication. Judging FSTs is a highly subjective process, which has led to countless false DUI accusations.

Subjective FSTs Equals False DUI Charges

  • Accuracy rates among studies vary widely. So in an effort to provide law enforcement with roadside tools for assessing the suspicion of DUI, the National Highway Traffic Safety Administration (NHTSA) developed standardized testing procedures for the top three FSTs: Horizontal Gaze Nystagmus (HGN), Walk and Turn, and One Leg Stand (watch these FSTs). The goal was to develop a consistent reliable point system and properly train law enforcement to administer standard procedures. However, the new point system is still subjective.
  • Studies show that the three standardized FSTs were found to only be 65-77% effective, leaving their results open to dispute in court proceedings. (NHTSA studies had a higher accuracy rate for these tests. Which are right?)
  • Also, the National Highway Transportation Safety Administration (NHTSA) admits if “any of the standardized field sobriety test elements is changed, the validity is compromised.” According to the National Association of Criminal Defense, “a number of courts have held that if not properly administered, the SFSTs are not admissible.”
  • Given the inaccuracy of roadside sobriety tests, many people are wrongly accused of DUI. Moreover, very few officers actually conduct roadside sobriety tests in accordance with established procedures.