Driving After the Use of Narcotic Substances – Legal Framework, Evidence and Procedural Specifics

I. Criminal Law Regulation and the Principle of “Zero Tolerance”

Driving a motor vehicle after the use of narcotic substances constitutes a criminal offense under Article 343b, paragraph 3 of the Bulgarian Criminal Code. Bulgarian criminal law adopts a “zero tolerance” model, under which no specific concentration threshold is required, nor is it necessary to prove an actual degree of impairment.

Unlike alcohol-related offenses, where statutory concentration limits exist, any detected amount of a narcotic substance is sufficient to trigger criminal liability. It is not necessary to establish actual incapacity to drive or the occurrence of danger; the mere presence of a substance included in the legally defined list is sufficient.

This legislative approach is justified by the absence of a universally recognized and objective medical method capable of determining the degree of impairment and the functional fitness of the driver at the relevant time.

II. The Legal Concept of “Narcotic Substance”

For criminal law purposes, narcotic substances are those included in the lists contained in the Final Provisions to Council of Ministers Decree No. 9 of 27 January 2022 amending the Ordinance on the Procedure for Classifying Plants and Substances as Narcotic, adopted by Decree No. 293 of 2011.

Therefore, criminal liability depends not on the general medical definition of a narcotic, but on its explicit inclusion in the statutory lists. If a substance is not listed, its presence in the driver’s body cannot form the basis for liability under Article 343b(3) of the Criminal Code.

III. Classification of Narcotic Substances

The substances are divided into three groups:

• High-risk substances prohibited for medical use – including amphetamines, cannabis, hashish, LSD, methamphetamines, coca leaves, and others.
• High-risk substances permitted for medical use – including codeine, morphine, hydrocodone, and benzodiazepines (e.g., diazepam).
• Risk substances permitted for medical use – such as alprazolam.

It is important to note that some of these substances are components of widely prescribed medications. Consequently, a driver may test positive following lawful medical treatment without intending narcotic use in the common sense.

IV. Police Testing – Conditions and Procedure

Criminal liability requires actual driving of a motor vehicle on a public road. Being inside a parked vehicle with the engine off does not constitute driving.

Before conducting a test, police officers prepare a protocol describing observed behavioral indicators suggesting drug use.

V. Technical Testing Method

Testing is performed using approved single-use kits and includes:

• Collection of an oral fluid sample;
• Placement of the sample in a container;
• Immersion of a test strip marked with identification data;
• Visual reading of the result via a control indicator.

A control line confirms test validity. The absence of a line opposite a specific substance indicates a positive result. The sample must then be sealed.

VI. Refusal and Chemical-Toxicological Examination

The driver is legally obliged to cooperate. In case of refusal, dispute, invalid sample, or impossibility to provide one, a referral for chemical-toxicological testing is issued.

The procedure includes:

• Two blood samples (one control sample);
• One urine sample;
• A medical protocol describing the driver’s condition;
• Storage of samples for up to one year.

The results are documented in an expert report and forwarded to the investigative authorities. The individual may request a repeat analysis at their own expense.

VII. Procedural Violations and Evidentiary Value

Failure to comply with statutory testing methodology may render the expert report inadmissible as evidence. For example, conducting only one analysis without a second confirmatory analysis may constitute a procedural violation.

Such violations may lead to exclusion of evidence and possible acquittal.

Conclusion

Driving after the use of narcotic substances constitutes a criminal offense whenever any concentration of a listed substance is detected. The law does not require proof of actual impairment.

Given the strict liability regime and complex evidentiary standards, strict procedural compliance is crucial for the outcome of the case.

This article does not constitute legal advice or a legal opinion by Attorney Mihail Tomov and is not related to any specific case. For legal assistance, consultation with a criminal defense attorney is required.