Yes.
In fact, a medical certificate merely represents a simple presumption of illness which may be overturned by the employer on the basis of any proof to the contrary, in particular by a medical counter-examination.
Thus, when the employer has doubts as to the reality of the employee’s illness or if he suspects that he has been given a medical certificate of convenience, he may ask the employee to submit, even during the period of medically certified sickness, to a medical counter-examination by a doctor having the same specialisation as the attending physician, or by a general practitioner.
The doctor chosen by the employer may be established in the Grand Duchy of Luxembourg or in the employee's country of residence. The employer may also send the doctor to the employee’s home.
In such case, the doctor’s fees are to be borne by the employer.
Nota Bene
The employee may not refuse to submit to the counter-examination without valid reasons.
However, the employer must allow the employee a reasonable amount of time to present himself to the doctor. The employee may not, even during the sickness and without valid reasons, refuse to be seen by the doctor chosen by the employer.
At the present time, it is not clear what the court considers to be valid reasons, but it is clear that each case will be examined individually based on the employee's personal situation.