Drug Testing in the Workplace: Legal Boundaries Under KVKK and Labor Law

Personal Data Protection and the Requirement of Explicit Consent The balance between ensuring occupational safety and protecting personal data forms a critical legal foundation regarding drug and alcohol testing in professional life.
To process such data, the explicit consent of the employee or job candidate is mandatory.
While employers do not have the authority to impose these tests without consent, it remains at the employer's discretion whether to hire candidates who refuse the test.
Clauses regarding testing added to employment contracts only gain validity through the detailed informing and approval of the worker.
It is a legal obligation for employers to act in accordance with the principle of transparency during this process.
Mandatory Audits in Strategic Professions In high-risk sectors such as aviation, transportation, nuclear energy, security, and firefighting, the implementation of drug and psychotechnical tests is of great importance for occupational health and safety.
In these fields, an employer's request for testing is based on a legitimate justification, as it aims to ensure public safety and prevent workplace accidents rather than infringing on individual rights.
However, it is essential to avoid the arbitrary use of this authority and to apply it only in situations appropriate to the nature of the work.
Concrete Suspicion and Termination of Employment Article 25 of the Labor Law grants employers certain powers if an employee comes to the workplace under the influence of drugs or uses these substances at work.
In the presence of concrete suspicion, an employer may request a test.
However, for an employment contract to be terminated due to addiction, it must be established that the condition continuously prevents the employee from performing their duties and that treatment is not possible.
In such health-based terminations, the employer's obligation to pay severance remains.
Employers may face serious legal sanctions in cases of unlawful processing of sensitive health data or discriminatory treatment based on such data.