Highway Code

Drug driving, a circular loosens the grip but risks remain (even on drugs). MIT confirms tests

However, it must be ascertained whether the driver is still under the influence of narcotic or psychotropic substances. Meanwhile, the Consulta is awaited

by Guido Camera, Stefano D'Errico* and Elio Santangelo*

7 May 2025

4' min read

4' min read

Just a few months after its entry into force, the new offence of driving after taking narcotic or psychotropic substances - introduced by the reform of the Road Code (law 177/2024) by amending Article 187 - confirms its critical aspects. So much so that, in a circular dated 11 April 2025, the Ministries of the Interior and Health issued guidelines on detection procedures, on the assumption that the offence can be said to be integrated on the sole condition that 'the substance still produces its effects in the body while driving'.

This is no small thing. In fact, it means recovering the requirement of the state of psycho-physical impairment suppressed a few months ago. Before 14 December 2024, the offence was to have created danger by driving in a psycho-physical altered state: after that date, it became mere assumption (except for the offences of homicide and road traffic injuries - serious or very serious - for which the requirement of altered state remains). But risks remain both general and for those taking medicines.

Risk of unconstitutionality

The reform may lead to discriminatory arbitrariness and strict liability. Will it be enough for judges to follow an adaptive interpretation such as that of the circular? The Constitutional Court will decide in the coming months.

In fact, by order of 8 April 2025, the Court of Pordenone raised the question of constitutionality before the Constitutional Court, considering:

- "manifestly unreasonable and unfair" to define as criminally relevant the mere positivity of a subject to the substance, without any investigation of the effects on driving ability;

- Unfairly equating entirely disparate situations (the road-safety-neutral conduct of someone who has taken substances but is perfectly lucid while driving and that of someone who actually drives while impaired);

- "objective" and "insuperable" the "uncertainty" of the rule, lacking "parameters to which to refer" in order to make the person concerned understand the consequences of his conduct;

- violated the principle of offensiveness and materiality of the fact, due to the abandonment of the 'logic of the lesion of the protected legal asset', in favour of the punitive paradigm of the 'criminal law of authorship'.

Moreover, observes the referring judge, in judgement 277/2004, the Constitutional Court had ruled out the unconstitutionality of the previous Article 187, precisely because of the presence of the requirement of a state of altered state resulting from the employment.

Drugs and Medicines

Questions remain on the assessments, which also concern drivers taking drugs that can affect driving ability. Legislative Decree 59/2011, Annex III, in fact refers the assessment of fitness to drive to the local medical commission. Due consideration must be given to this rule for a more complete future examination of the subject, also to ensure homogeneity at a national level.

The circular of 11 April indicates the toxicological-forensic assessment procedures for alcohol (Articles 186 and 186-bis of the Code) and narcotic or psychotropic substances (Article 187). With regard to substances, the circular indicates that:

- "it is necessary to prove that the narcotic or psychotropic substance was taken in a period of time approximate to the driving of the vehicle, such that it may be presumed that the substance is still producing its effects in the body while driving";

- blood and saliva are the biological liquids deemed suitable for such a test, whereas a urine positivity would not be 'indicative of ongoing intoxication'.

But the correlation between positivity detected on blood or saliva and 'an ongoing intoxication' may not always be a safe and reliable data in the medico-legal field. The circular gives the indication to adhere to the Guidelines of the Italian Group of Forensic Toxicologists (Gtfi) as a 'technical-scientific reference'. Thus, homogeneous methods of ascertainment would be adopted to ensure the reliability of the data. But the Gtfi reports that the cut-offs used to establish the negativity/positivity of the sample 'are not interpretive cut-offs', so a detected positivity does not necessarily correlate with the existence of effects of the substance on the driver.

On the other hand, the choice of a certain cut-off may impact the detectability time of a substance in biological fluids. Generally speaking, the lower the cut-off value adopted, the longer the period correlated with a possible positive outcome of the analyses may be, without this necessarily indicating the actuality of the intoxication.

The circular addresses three other relevant issues. The first is the possibility of acquiring information on any pharmacological therapies carried out by the driver (declared or certified), which should 'allow a more complete evaluation and interpretation of the results of the second-level toxicological tests', without specifying who and how this evaluation and interpretation should be carried out.

The second relates to narcotic and psychotropic substances and the reference to Presidential Decree 309/1990, a regulatory source subject to continuous updating where, in addition to substances 'linked to the sanctions system for illicit uses', there is currently a list of over 100 medicines that can therefore be potentially investigated.

The third relates to the medical record for assessing the driver's psycho-physical state. In the case of homicide or serious or very serious road injuries, a doctor is expected to perform a specific objective examination, which, however, does not result in a documented diagnostic summary of the existence or non-existence of a psycho-physical state of impairment. Moreover, this conduct is not always identifiable contextually to the claims, but could be later. Hence, this possible criticality of the ascertainment phase must be pointed out as of now.

In the meantime, a note from the MIT states that 'the directive regulating the modalities of controls on drug use was adopted on 11 April in full coherence with the new rules that aim to punish those who drive after taking drugs and overcoming the (subjective and untestable) concept of "state of alteration". It is worth remembering that the deputy prime minister and minister Matteo Salvini reiterated that drug taking is quite different from the use of drugs, including cannabinoids, with the aim of not penalising those undergoing medical treatment'.

*Complex Unit Forensic Medicine, Julian Isontine University Health Authority