When arrested for a DUI, an individual may be requested to perform certain tests to determine their sobriety. These can include breathalyzers or blood tests. Breathalyzer tests are wrought with problems and often produce inaccurate results.  Blood tests are usually more accurate, however, depending on the circumstances surrounding the procedure that was followed when blood was drawn, there may be evidentiary challenges to the admissibility of the blood test result.  A skilled and experienced attorney knows where the weaknesses lie in each test and could help you challenge inaccurate Charleston DUI breath and blood tests.

How are Breath Tests Administered in Charleston?

The breathalyzer testing machine detects alcohol molecules in an individual’s breath, which is presumed to correlate to an individual’s blood alcohol content. In Charleston and throughout South Carolina, the breathalyzer testing device used by law enforcement is the DataMaster machine.

In Charleston, a breathalyzer test administration should be recorded on video. An individual should be advised of their implied consent rights, most importantly their right to refuse the test. After a 20-minute waiting period, during which time the individual is observed on camera and in person by the arresting officer, the machine will be ready to accept the breath sample. If the individual has consented to the test, they will blow into the machine until it issues a reading of the individual’s blood alcohol content. This could take 15 to 20 seconds depending on how hard the individual blew or how much alcohol is in their system. There are specific, acceptable sample parameters for the DataMaster machine that should be met in order for a court to deem the sample admissible.

Finding a Sample Invalid

South Carolina has a list of policies and procedures that must be followed for breath samples to be considered valid. Additionally, the DataMaster machine has manufacturer guidelines that must be followed. A failure to follow proper procedures could render a test result invalid.

Additionally, radio interference from an arresting officer’s cellphone or activated body camera could render the breath sample invalid. Officers could also contaminate the mouthpiece on the tube connected to the DataMaster by touching it with their hands before the test is administered.

When Can a Blood Test be Requested?

Under most circumstances, for blood to be drawn legally, an arresting officer must have a search warrant. However, if an individual is being charged with felony DUI, there is a state statute permitting an officer to obtain a blood sample from them.  Currently, there is a conflict in the law on this issue in South Carolina. Officers also have the right to request a search warrant for an individual’s blood if it is suspected that the individual is under the influence of drugs rather than alcohol. The blood test must occur at a medical facility by a licensed medical professional who is responsible for properly obtaining, storing, and preserving the sample.

Accuracy Determining BAC

If all of the proper policies, procedures, and protocols are followed, blood tests can accurately determine an individual’s BAC. If those policies and procedures are not followed, there is interference with the blood sample, or the sample is not stored properly, the blood sample may not be reliable enough to be admissible in court.

Accuracy Determining Drug Impairment

Blood tests conducted under the proper protocols could accurately determine the presence of a drug in an individual’s system. However, the mere presence of a drug does not necessarily mean an individual is impaired. An experienced defense attorney could have a toxicologist review how much of the drug is in the blood sample, and based on the individuals’ physical characteristics, age, height, and weight, determine if the quantity of that drug would be suggestive of impairment.

How a DUI Lawyer Could Help

A seasoned Charleston attorney could challenge multiple aspects of the breath or blood test process. Whether law enforcement improperly executed a search warrant, had an unqualified medical professional perform the blood draw, or incorrectly stored the sample, a knowledgeable attorney could explore all possible avenues through which the results of a test could be challenged. Call today and schedule your first consultation.