The Court of Cassation validates the use of saliva tests without proof of their reliability

A key decision for the legal framework of roadside drug screenings

On March 12, 2025, the Court of Cassation issued an important ruling that clarifies the legal framework for saliva drug screening tests conducted by law enforcement. The ruling (appeal no. 24-82.925) overturns a decision by the Rennes court of appeal that had annulled a procedure on the grounds that the police had not provided precise information on the reliability of the test used.

This decision could have a direct impact on road checks, as well as on debates surrounding prevention and the fight against drug use while driving.

The facts of the case: an acquittal overturned by the Court of Cassation

The case involved a driver stopped in February 2019 by the gendarmes, who conducted a saliva test revealing the presence of drugs. Based on this screening, samples were taken and confirmed the positive result.

Convicted at first instance, the driver had won the case on appeal, the court having ruled that the lack of precise information about the test (brand, batch number, expiration date) prevented verification of its reliability.

The Attorney General then filed an appeal to the Court of Cassation, contesting this annulment.

Why did the Court of Cassation overturn the decision of the court of appeal?

The Court of Cassation relied on Articles L. 235-1 and L. 235-2 of the Highway Code to make its decision. According to these texts:

• Saliva screening tests are only used to presume drug use.
• They allow authorization of a biological sample which can then irrefutably establish the offense.
• The law enforcement is not required to prove the reliability of the saliva test, nor to specify its technical references.

The Court of Cassation therefore ruled that the court of appeal had made a legal error by annulling the procedure for a reason that was not legally justified.

Outcome: the decision is overturned and the case will be retried.

What are the consequences for motorists and road safety prevention?

This decision strengthens the legitimacy of saliva tests, which are now indisputable, even if their reliability is not proven case by case. This raises several questions:

• From a legal standpoint
  From now on, a positive test will be hard to challenge in court, except in cases of clear procedural errors. This strengthens law enforcement powers but may also reduce defense options for drivers.

• Regarding test reliability
  Some experts worry that a saliva test can detect traces of substances consumed several days earlier, without necessarily indicating impairment at the time of testing.

• From a prevention perspective
  This decision highlights the importance of raising more awareness rather than limiting to a strictly punitive framework. Indeed, many drivers do not know how long drugs remain detectable in their system, which can expose them to a positive test even if they no longer feel the effects.

Screening and prevention: what balance?

Drug screening while driving is primarily a road safety measure aimed at protecting users. However, its effectiveness also depends on driver education and awareness.

💡 Some key facts to remember:

• Cannabis can be detected up to 24 hours after consumption, or even longer in cases of regular use.
• Cocaine and amphetamines remain on average 12 to 24 hours in saliva.
• Unlike alcohol, where the effect is directly measurable in mg/L of blood, drug tests do not indicate whether a driver is still under the influence or has simply consumed recently.

A responsible approach to avoid repression

Rather than limiting ourselves to sanctions, it is essential to develop prevention tools:

✔️ Inform about drug detection times
✔️ Encourage self-testing before driving
✔️ Train companies and event organizers in prevention

With this in mind, AMA Prévention offers reliable screening tests as well as awareness solutions to prevent risks before they lead to sanctions.

Conclusion

The ruling of March 12, 2025 marks a turning point in case law on drug screening. It strengthens the enforcement framework while raising questions about driver prevention and information.

While screening remains essential to ensure road safety, it is equally crucial to support these measures with appropriate awareness to prevent risky behaviors and reduce offenses rather than just punish them.

We value your feedback!

What do you think of this decision? Should prevention be strengthened? Share your opinion in the comments! 💬🚗

💡 To go further:
📌 Articles L. 235-1 and L. 235-2 of the Highway Code → Legifrance
📌 Full decision of the Court of Cassation → Court of Cassation

About AMA Prevention

A committed player in risk behavior prevention, AMA Prévention supports companies, event organizers, and individuals with screening and awareness solutions.

Find our resources on ama-prevention.fr 🚀

💡 Practical information on screening

During a roadside check, the gendarmerie saliva test is commonly used to detect the presence of drugs. Many wonder about how long the gendarmerie saliva drug test stays positive: it depends on metabolism, but THC remains detectable from several hours up to a few days. The gendarmerie THC saliva test (or gendarmerie saliva THC test) specifically targets recent cannabis use.

For prevention at home or in the workplace, taking a THC saliva test (also called a saliva THC test) is an excellent step. If you’re looking to equip yourself, you might be wondering where to buy an equivalent gendarmerie saliva test? Although it can sometimes be hard to find a THC saliva test at a pharmacy, you can order our professional devices directly online.