FMCSR 392.4(b): Drug Possession Citation – Driver Q&A

Our inspection records show zero citations recorded for FMCSR 392.4(b) drug possession across our database of 13 million inspections. This makes direct comparison difficult, but peer violations in the controlled substances category show out-of-service rates ranging from 95.9% to 98.5%. Given the severity of drug possession charges, similar codes are nearly always grounds for immediate OOS placement. If you've received this citation, expect your vehicle to be placed out of service pending resolution.

FMCSR 392.4(b) carries a CSA severity weight of 10 points. Your total 30-day CSA impact depends on how many times you're cited in that window—each citation gets the full 10-point value. For context, controlled substance violations are among the highest-weighted BASIC violations in the CSA system, reflecting the serious safety and legal implications of drug possession in commercial transportation.

Immediate steps:

1. Do not operate your vehicle—expect an out-of-service order.
2. Contact a commercial transport attorney immediately; drug possession has criminal implications beyond the citation.
3. Notify your employer/fleet manager if you're a company driver.
4. Document the inspection scene (officer name, time, location, any witnesses).
5. Request the inspection report and violation details from the enforcement agency.
6. Preserve all evidence related to the substance found (possession proof, chain of custody).
7. Do not discuss the citation with anyone except your attorney.

This is both a regulatory and potential criminal matter—legal counsel is essential.

Across our inspection records, peer drug and substance violations show out-of-service rates of 95.9% to 98.5%, with similar codes accumulating thousands of citations annually. For example, 392.4A-DOSP (use of drugs) generated 3,947 citations with a 95.9% OOS rate, while 392.4A-DOSU (use of drugs) reached 1,648 citations at 98.5% OOS. Possession is treated as seriously as use in the enforcement data—both carry near-certain out-of-service placement and are among the highest-severity FMCSR violations.

Yes, you can challenge a citation through the DataQs Registry Docket Review (RDR) process, which allows drivers and carriers to dispute factual errors in roadside inspection records. However, contestability depends on the type of finding: documentation and procedural errors (officer did not follow protocol, inaccurate recording of facts) are more defensible than direct observation of controlled substances. You have 30 days from the inspection date to initiate a DataQs challenge. Work with your attorney to determine if you have grounds before submitting.

Our database of 13 million inspections shows zero recorded citations for FMCSR 392.4(b) in the all-time record, last 12 months, and last 90 days. This is unusual and suggests either extremely rare enforcement of this specific code, or that possession charges are typically handled through criminal channels rather than FMCSR citations. Related codes—use of drugs (392.4A variants) and alcohol possession (392.5 variants)—are far more common, collectively totaling over 12,000 citations. If you've received a 392.4(b) citation, it represents a rare and serious enforcement action.

Yes. Drug possession violations appear on your Safety Management System (SMS) record and your commercial driver's license history. Prospective employers conduct background checks that include FMCSA enforcement records, and a 392.4(b) citation—especially paired with criminal charges—will be visible for years. Many carriers have zero-tolerance policies for controlled substance violations. Beyond employment, this violation can affect your CDL renewal status and may result in disqualification depending on the substance and your state's regulations.

Both are drug-related violations, but 392.4(a) (use of drugs) has recorded 3,919 citations in our database with a 96.9% out-of-service rate, while 392.4(b) (possession) shows zero citations. The regulatory distinction is important: possession is carrying a controlled substance while on duty or operating a CMV, while use is actually consuming it. In enforcement practice, use violations are cited much more frequently. If you're facing a 392.4(b) charge, the absence of precedent citations may reflect that possession cases are often prosecuted criminally rather than cited under FMCSR alone.