§ 50–2206.51. Evidence of impairment.

(a) If as a result of the operation or the physical control of a vehicle, or a watercraft, a person is tried in any court of competent jurisdiction within the District of Columbia for operating or being in physical control of a vehicle, or a watercraft, while under the influence of alcohol in violation of § 50-2206.11, § 50-2206.12, or § 50-2206.31, negligent homicide in violation of § 50-2203.01, or manslaughter committed in the operation of a vehicle in violation of § 22-2105, and in the course of the trial there is received, based upon chemical tests, evidence of alcohol in the defendant’s blood, breath, or urine, such evidence shall:

(1) If the defendant’s alcohol concentration at the time of testing was less than 0.05 grams per 100 milliliters of blood or per 210 liters of breath or 0.06 grams or less per 100 milliliters of urine, establish a rebuttable presumption that the person was not, at the time, under the influence of alcohol.

(2) If the defendant’s alcohol concentration at the time of testing was 0. 05 grams or more per 100 milliliters of blood or per 210 liters of breath or more than 0.06 grams of per 100 milliliters of urine, but less than 0.08 grams per 100 milliliters of blood or per 210 liters of breath or less than 0.10 grams per 100 milliliters of urine, constitute prima facie proof that the person was, at the time, under the influence of alcohol.

(b) The rebuttable presumption contained in subsection (a)(1) of this section shall not apply if:

(1) There is evidence that the person is impaired by a drug;

(2) The defendant was operating or in physical control of a commercial vehicle; or

(3) The defendant, at the time of arrest, was under the age of 21.