South Dakota DUI Chemical Evidence

Requirements for valid chemical alcohol test:

Only a licensed medical professional may draw blood from the driver, but anyone whom has been licensed by the State may take a sample of the driver's breath or another bodily substance, as long as the testing process itself has been certified.

Interpretation of tests:

If a chemical test of a noncommercial driver's blood, breath, or other bodily substance reveals a BAC of 0.05 or less, the driver is presumed to not be under the influence. This means that unless the driver is proven to have been under the influence by some evidence which is more persuasive than the test result, the driver will be considered to have been sober. If the test reveals a BAC of at least 0.08 it is assumed that the driver was under the influence.

Type of tests used:

In South Dakota, the most common test for alcohol concentration is a blood test conducted at the state forensic chemistry laboratory. The laboratory tests samples of blood  for the concentration of alcohol with a gas chromatograph-mass spectrometer. In principle, these devices are basically filters which use known features about chemicals (molecular weight, for example) to cause each of the chemical compounds that makes up a sample to exit the device at a different time so that the detector can keep track of how much of each chemical (specifically ethyl and other low-weight alcohols in DUI investigations) the sample contains.

Field Sobriety Testing In South Dakota

Field sobreity testing is standardized throughout the United States. To learn about the various types of field tests and how they are interpreted, see the field sobriety test overview.