Who is entrusted with carrying out a divorce in the event of a woman marrying a boy or an insane person?

The divorce pronounced by a minor before puberty is not valid according to the majority of scholars, whereas the Hanbalis permit it for a discerning minor who comprehends the sacredness of his wife to him through divorce. The divorce pronounced by an insane person during his state of insanity is not valid; however, if he pronounces divorce while lucid, his divorce is valid. The father or anyone else is not permitted to act on behalf of the minor or the insane person in divorce according to the majority of scholars. Jurists have asserted the invalidity of divorce pronounced by the insane and the mentally incapacitated due to their lack of legal capacity. If there is a compelling reason to divorce the wife of a minor or an insane person, the one who undertakes the divorce is the Sharia judge.