Article R5211-29 of the French General Code of Local Authorities
When the commission is set up by the prefect, and after each general renewal of the municipal councils, the members of the commission appoint by secret ballot and by an absolute majority a general rapporteur and two assessors from among the members of the commission elected by the representatives of the mayors. If, after two rounds of voting, no candidate has obtained an absolute majority, a third round is held…