South Dakota Internal Possession Doctrine — SDCL § 22-42-5.1 (Schroeder / Whistler)

Last verified: May 2026

The Statutory Foundation — SDCL § 22-42-1(1)

In 2001, the South Dakota Legislature amended the definition of "controlled substance" in SDCL § 22-42-1(1) to include "an altered state of a drug or substance absorbed into the human body." The amendment’s significance: it transformed the language of "possession" from physical custody of a drug to chemical custody — the metabolites circulating in a person’s bloodstream after consumption.

State v. Schroeder, 2004 S.D. 21 — The Foundational Case

In 2004, the South Dakota Supreme Court upheld a possession conviction under SDCL § 22-42-5 (unauthorized possession) where the only evidence presented at trial was a positive urinalysis. The defendant had been arrested on an unrelated matter; the urinalysis was performed at the jail. No physical drug was found. The conviction stood.

The Schroeder court reasoned that the 2001 amendment to § 22-42-1(1) clearly extended "possession" to chemical possession, and the urinalysis result was sufficient evidence of "possession" of the metabolite.

State v. Whistler (2014) — Reaffirmation

A decade later, in State v. Whistler, the SD Supreme Court reaffirmed Schroeder and rejected the argument that an ingestion conviction under SDCL § 22-42-5.1 precludes a separate possession conviction under § 22-42-5. The decision means that a single act of cannabis use can produce both an ingestion charge and a separate "internal possession" charge.

The Three Statutes That Stack

• SDCL § 22-42-5 — Unauthorized possession (the statute used in Schroeder/Whistler on metabolites). Class 1 misdemeanor.
• SDCL § 22-42-5.1 — Unauthorized ingestion of controlled drug or substance. After SB 83 (effective July 1, 2025), first/second offense = Class 1 misdemeanor; third+ within 10 yrs = Class 5 felony.
• SDCL § 22-42-15 — Ingesting substance "for the purpose of becoming intoxicated" (excluding alcoholic beverages). Misdemeanor.

March 12, 2025 — SB 83 Penalty Downgrade

Gov. Larry Rhoden signed Senate Bill 83 on March 12, 2025 (effective July 1, 2025), reducing first- and second-offense ingestion under SDCL § 22-42-5.1 from a Class 5 felony (up to 5 years, $10,000 fine) to a Class 1 misdemeanor (up to 1 year, $2,000 fine). Third and subsequent offenses within 10 years remain felonies. The change was not retroactive — pre-July 2025 ingestion charges remain felonies.

Cardholder Protection — SDCL § 34-20G-24

Registered medical-cannabis cardholders are partially protected. SDCL § 34-20G-24 specifies that "a registered qualified patient may not be deemed to be under the influence of cannabis simply due to the presence of cannabis metabolites or components in inadequate concentration to induce impairment." This is meaningful protection for cardholders — but it does not displace the §32-23-1 5 ng/mL DUI threshold or the §22-42-5/5.1 ingestion-prosecution framework for non-cardholders.

Cross-Border Implications

The most consequential consequence of the doctrine: A South Dakota resident who travels to Minnesota or Montana, legally consumes cannabis there over a weekend, and returns home can — if drug-tested or stopped by police — face an ingestion charge under SDCL § 22-42-5.1 or possession charge under § 22-42-5 even though no physical cannabis is in their possession or system at the moment of stop.

Post-SB 83 (effective July 2025), the first two such offenses are Class 1 misdemeanors rather than felonies, but the unique exposure remains. Out-of-state visitors transiting South Dakota with legal Minnesota or Montana cannabis are in violation of both federal interstate transport law (21 U.S.C. § 841) and SD’s § 22-42-6 possession statute.

Practical Notes

• The internal-possession doctrine is unique. Most other states do not prosecute on metabolite-only evidence.
• Even out-of-state legal use creates SD exposure. Travel + drug test or stop = potential ingestion or possession charge.
• Cardholders are protected from impairment-presumption. But not from DUI prosecution above 5 ng/mL THC.
• Schroeder and Whistler remain good law. SB 83 reduced penalties but did not abrogate the doctrine.
• Get counsel immediately if charged with ingestion. The legal questions are technical and the penalties are real.

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