While the employer is entitled to monitor the activity of their employees, some means of control are illegal if they are implemented without the employees’ knowledge.
This is the case of a surveillance by a private detective.
In a recent decision, the French Supreme Court held that having an employee followed by a private detective to establish that the employee is not complying with his non-competition obligation trespasses the employee’s private life, even if it had only lasted a few hours and even if the detective’s observations were made in a public place.
In this respect, the French Supreme Court differs from the administrative case law which had considered it to be lawful to impose a sanction on the basis of a surveillance report drawn up by a private investigator against a public servant provided the report was based on material observations of the servant’s conduct as part of his activity and in places open to the public.
French Supreme Court, 26 September 2018, n°17-11.122