Drug DWI in North Carolina: marijuana, prescriptions and the Schedule I rule

Three ways to prove DWI, and where drugs fit

“DUI” is the everyday word and “drugged driving” is the search term; the North Carolina charge is driving while impaired, DWI, and the same statute covers alcohol, marijuana, prescriptions and everything else.

G.S. 20-138.1(a) makes it an offense to drive a vehicle “upon any highway, any street, or any public vehicular area within this State” in any of three conditions:

Drug cases live under prongs one and three. Prong two is written around “alcohol concentration,” which G.S. 20-4.01(1b) defines as grams of alcohol per 100 milliliters of blood or per 210 liters of breath; nothing in the statute translates that into a drug number. For marijuana that means there is no legal THC limit in North Carolina the way there is a 0.08 for alcohol — the question is whether you were under the influence, unless the third prong applies. Subsection (b1) preserves your right to argue “that a chemical analysis result is inadmissible,” and subsection (d) makes the offense a misdemeanor sentenced under G.S. 20-179. The statute reaches “any relevant time after the driving,” so a blood draw taken after the stop can still be the State's evidence.

Schedule I versus every other drug

The third prong turns a lab report into the whole case: “any amount” of a Schedule I substance “or its metabolites” — the compounds the body makes as it breaks a drug down — in blood or urine is impaired driving, without any showing that you drove badly or felt anything. The list of Schedule I substances is in G.S. 90-89; this guide has not reproduced it and does not state which drugs are on it. Whether the substance in your report is Schedule I is the first question a lawyer will answer.

Every other schedule, and every substance that is not scheduled at all, falls back to prong one, where the State must prove you were “under the influence of an impairing substance.” The commercial-vehicle statute, G.S. 20-138.2, carries the identical Schedule I prong for commercial motor vehicles. The under-21 statute, G.S. 20-138.3, reaches a driver “while he has remaining in his body any alcohol or controlled substance previously consumed” — with an exception for a controlled substance “lawfully obtained and taken in therapeutically appropriate amounts.” That exception is written into the under-21 statute; G.S. 20-138.1 has no equivalent. The under-21 page covers Duke and NCCU students charged under it.

How a drug DWI is investigated

A drug case has no roadside number, so the investigation leans on observation, then on blood.

1. The stop and the roadside tests

   The officer needs reasonable and articulable suspicion for the stop and probable cause for the arrest. The standardized field sobriety tests — horizontal gaze nystagmus, walk-and-turn and one-leg stand — are the usual roadside evidence. The handheld alcohol screening test under G.S. 20-16.3 measures alcohol only; a screening that shows no alcohol alongside signs of impairment points the investigation toward drugs.

2. The arrest, the rights and the request for blood

   DWI is an implied-consent offense. Under G.S. 20-16.2 the officer or chemical analyst “shall designate the type of test or tests to be given,” and G.S. 20-139.1(b5) allows a request for “a chemical analysis of the person's blood or other bodily fluid or substance...in addition to or in lieu of a chemical analysis of the breath.” The rights read to you warn that “an officer can compel you to be tested under other laws,” and refusing blood is a willful refusal with its own 12-month revocation — see the refusal page. If you are unconscious, the officer “may direct the taking of a blood sample.”

3. The draw

   Blood is drawn by “a physician, registered nurse, emergency medical technician, or other qualified person.” Who drew it, when, and how the tube was handled and labeled are the chain-of-custody facts a lawyer checks against the paperwork.

4. The magistrate and the hold

   You go before a magistrate at the Durham County Detention Facility, 219 S. Mangum St., for the initial appearance. G.S. 15A-534.2 lets the magistrate hold you while impaired, for no longer than 24 hours, until “The defendant's physical and mental faculties are no longer impaired to the extent that he presents a danger” or “A sober, responsible adult is willing and able to assume responsibility for the defendant.” The 30-day civil revocation is triggered by an alcohol concentration or a refusal, not by a drug result — G.S. 20-16.5(b)(4) lists no drug trigger — so a cooperative blood draw in a drug-only case does not start it. The license page has the rules.

5. The State Crime Laboratory

   The sample goes to a laboratory for toxicology, and the result is what the State builds prong one or prong three on. If you are convicted after a lab tested your “bodily fluids...for the presence of alcohol or controlled substances,” G.S. 7A-304(a)(7) requires the judge to “order payment of the sum of six hundred dollars ($600.00)” for the State Crime Laboratory — a local government or hospital lab fee is also $600 — in addition to the $293 in ordinary district court costs for a DWI conviction. The lab's report may come in by affidavit unless you object “at least 15 business days before the proceeding at which the affidavit would be used.”

The same sentencing levels and license rules apply

A drug DWI is sentenced under G.S. 20-179 exactly like an alcohol DWI: a sentencing hearing, grossly aggravating factors first, then the weighing that lands on Level Five through Aggravated Level One. The penalties page has the table. Three factor details are drug-specific. Aggravating factor (1) is “Gross impairment of the defendant's faculties while driving or an alcohol concentration of 0.15 or more,” so gross impairment counts without a number. Mitigating factors (1) and (2), slight impairment, are limited by their words to impairment “resulting solely from alcohol.” And mitigating factor (5) is the prescription factor: “Impairment of the defendant's faculties caused primarily by a lawfully prescribed drug for an existing medical condition, and the amount of the drug taken was within the prescribed dosage.”

The license consequences follow the conviction, not the substance. The DMV revokes for one year on a first conviction under G.S. 20-19(c1); a limited driving privilege under G.S. 20-179.3 needs Level Three, Four or Five, no prior within seven years and “a substance abuse assessment of the type required by G.S. 20-17.6”; and the ignition interlock under G.S. 20-17.8 is triggered by an alcohol concentration of 0.15 or more, a prior within seven years, or Aggravated Level One — the first trigger cannot arise in a drug-only case. Restoration needs the DHHS certificate of completion and the $167.25 fee. NCDHHS calls the assessment a “substance use assessment,” the fee is $100 under G.S. 122C-142.1, and Durham providers such as Genesis DWI Services, 118 East Main Street, and El Futuro, 2020 Chapel Hill Rd. Suite 23, are on the state's list. A first-offense DWI works the same way whether the substance was alcohol or a drug, and a conviction cannot be expunged.

Prescription drugs: not a defense, but a factor

The statute closes the door on “but it was prescribed” at the guilt stage. G.S. 20-138.1(b): the fact that a person “is or has been legally entitled to use alcohol or a drug is not a defense.” What a prescription can do is narrower. At sentencing, mitigating factor (5) applies where impairment was “caused primarily by a lawfully prescribed drug for an existing medical condition, and the amount of the drug taken was within the prescribed dosage” — and the defendant carries the burden of proving a mitigating factor “by the greater weight of the evidence.” If a jail term is ordered, G.S. 20-179(s) says you will be “refused entrance and shall be reported back to court” if you arrive with alcohol or a controlled substance in your body, “unless lawfully obtained and taken in therapeutically appropriate amounts” — the one place in the DWI statute where a prescription taken as directed is expressly allowed for.

If a drug was prescribed to you, the questions a lawyer will ask are whether you were within the dosage, whether the State's evidence shows impairment at all, and whether the substance is Schedule I. What a Durham DWI lawyer costs is on its own page.