Explanation:
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http://www.bcf.asso.fr/system/files/Guide_indemnisation_EN_o...

2. Expert medical evaluation
a) Designation
The experts charged with evaluating the bodily harm are independent physicians having received special training in legal redress for cases of bodily harm. They hold State diplomas
and are most often assigned at the request of the insurers in the framework of the compensation procedure set down in law.
The may also be appointed by the courts in the case of judicial proceedings. The victims may request assistance from a physician.

b) The role of the expert physician
His brief normally consists in determining certain areas of indemnifiable loss and to provide an opinion on the sequellae which are directly related to the accident (see assignments ...).
Thus, after evaluation of the bodily harm by the physician, the insurer establishes a monetary evaluation.