6.10 Field Identification of Controlled Substances & Fentanyl Exposure Safety
Key Takeaways
- POST Unit V.O, Basic Patrol Controlled Substance Identification and Investigations, is a 4-hour required block inside Patrol Procedures.
- Presumptive color-reagent field tests establish probable cause only; a confirmatory laboratory analysis is required before a case is filed on substance identity.
- Officers should never field test suspected fentanyl or unknown powders; the correct practice is to seal, document, and send the item directly to the laboratory.
- Colorado's Good Samaritan provision in C.R.S. 18-1-711 grants limited immunity from certain drug possession charges for a person who in good faith reports an emergency drug or alcohol overdose event and remains at the scene.
- Naloxone administration by peace officers is authorized in Colorado, and CDC and NIOSH guidance is that incidental skin contact with fentanyl does not cause overdose; wash with soap and water rather than using alcohol-based sanitizer.
Field Identification of Controlled Substances & Fentanyl Exposure Safety
Unit V.O — Basic Patrol Controlled Substance Identification and Investigations (4 required hours) sits inside Patrol Procedures rather than Basic Law, because POST treats drug recognition as a patrol competency rather than a legal one. The officer's job is not to prove chemistry; it is to recognize indicators, preserve the item, protect themselves, and write a report that supports a laboratory-confirmed charge.
1. Physical and Behavioral Indicators by Category
| Category | Common street forms | Paraphernalia | Behavioral / physiological signs |
|---|---|---|---|
| Central nervous system stimulants (methamphetamine, cocaine) | White to off-white crystal or powder; rock cocaine | Glass pipe with bulb, cut straws, razor blades, mirrors | Dilated pupils, elevated pulse and blood pressure, rapid speech, hypervigilance, bruxism, excited delirium risk |
| CNS depressants (benzodiazepines, barbiturates) | Pressed tablets, capsules | Pill bottles without labels | Slurred speech, ataxia, drowsiness, normal pupils |
| Narcotic analgesics (heroin, fentanyl, oxycodone) | Tan to brown powder, black tar; blue "M30" counterfeit pills | Spoons, cotton, tourniquets, foil with burn tracks | Pinpoint pupils, droopy eyelids, slow raspy speech, track marks, depressed respiration |
| Cannabis | Flower, wax, shatter, edibles | Grinders, dab rigs, vape carts | Odor, reddened conjunctiva, eyelid tremors, elevated pulse |
| Hallucinogens (LSD, psilocybin) | Blotter paper, dried mushrooms | Blotter sheets, small bags | Dilated pupils, disorientation, synesthesia reports, elevated pulse |
| Dissociative anesthetics (ketamine, PCP) | Clear liquid, off-white powder, dipped cigarettes | Small vials, chemical-smelling cigarettes | Blank stare, horizontal and vertical nystagmus, incomplete verbal responses |
The two vital-sign shortcuts POST expects: pinpoint pupils plus depressed respiration equals a narcotic and a medical emergency, and vertical nystagmus points to a dissociative anesthetic or high doses of a CNS depressant, not to alcohol alone.
2. Presumptive Field Testing: What It Proves and What It Does Not
Colorado agencies use color-reagent presumptive kits and, increasingly, handheld Raman or infrared analyzers. Their legal value is narrow:
| Question | Answer |
|---|---|
| Does a positive presumptive test establish probable cause? | Yes, in combination with the totality of circumstances |
| Does it establish identity for a criminal filing? | No. A confirmatory laboratory analysis is required |
| Can it distinguish hemp from marijuana? | No. Field tests detect THC but not the 0.3 percent delta-9 threshold |
| Does a negative result defeat probable cause? | Not necessarily, but the officer must document it |
Documentation rules. Record the kit lot number, the expiration date, the reagent used, the observed color change, the officer's training, and the exact wording of the result. False positives are well documented for common substances, and a report that says "tested positive for methamphetamine" without qualification is a cross-examination liability. Write "presumptive positive."
3. Fentanyl and Unknown Powders: Do Not Field Test
The controlling practice in Colorado and nationally is simple: suspected fentanyl, carfentanil, benzimidazole opiates and unidentified powders are not field tested. They are photographed in place, sealed in tamper-evident packaging with minimum handling, and submitted directly for laboratory analysis.
Exposure science matters because bad information produces bad tactics:
- CDC and NIOSH guidance is that incidental skin contact with fentanyl powder does not cause opioid toxicity; the risk pathways of concern are inhalation of aerosolized powder and mucous membrane contact.
- Do not use alcohol-based hand sanitizer after suspected contact; alcohol can increase dermal absorption. Wash with soap and water.
- Nitrile gloves, eye protection and, where powder may aerosolize, a fitted respirator are the standard precautions.
- Never conduct a field test in a closed vehicle, and never taste, sniff, or blow powder off a surface.
Naloxone. Colorado peace officers are authorized to carry and administer naloxone. Signs warranting administration are unresponsiveness with depressed or absent respiration and pinpoint pupils. Naloxone is given intranasally or intramuscularly, may require repeat dosing with high-potency synthetic opioids, and always requires EMS response because the opioid can outlast the antagonist.
4. Colorado's Overdose Good Samaritan Immunity — C.R.S. 18-1-711
Colorado grants limited immunity from arrest and prosecution for specified drug possession offenses to a person who:
- Reports in good faith an emergency drug or alcohol overdose event to a 911 operator, law enforcement, or medical provider;
- Remains at the scene until assistance arrives; and
- Identifies themselves and cooperates with responders.
The immunity also extends to the person who suffered the overdose. It does not immunize distribution offenses, outstanding warrants, or unrelated crimes. Officers must know this cold: an arrest that violates C.R.S. 18-1-711 both fails legally and destroys the public-health objective — people stop calling 911.
5. Packaging, Weighing and Report Content
FIELD HANDLING SEQUENCE
1. PHOTOGRAPH in place, with scale and case number visible
2. GLOVE UP; minimize handling; no field test on unknown powders
3. PACKAGE in tamper-evident, heat-sealed or evidence-taped container
4. LABEL: case number, item number, date/time, location, seizing officer
5. WEIGH at the station on a calibrated scale, packaging separated
6. LOG into evidence; request laboratory analysis
A report that supports a Colorado drug charge answers five questions explicitly: what the item is presumptively, where exactly it was found, who had knowledge and control, how much it weighed on a calibrated scale, and what indicia of use versus distribution were present. Weight decides the offense level in Colorado's drug grid, so an unweighed or estimated seizure is an unfiled case.
Officers respond to a report of an unresponsive person. A friend called 911, stayed on scene, identified herself, and admits she possesses a small amount of heroin. Under C.R.S. 18-1-711, how should officers proceed?
During a car stop an officer finds an unlabeled baggie containing an unknown white powder. What is the correct field practice?