Is it permissible for children to put a legal interdiction on their 84-year-old father, who is sometimes aware and sometimes does not recognize his children, and buys drinks at exorbitant prices from people who visit him from Oman?

The majority of scholars permit interdiction (hajr) over a mature man if he is not رشيدًا (of sound judgment) and does not manage his wealth well, or if he squanders it, or if he is insane, or has suffered a mental impairment such as a madman or an elderly person whose mind has become unsound due to old age. This is supported by the Almighty's saying: (فَإِنْ كَانَ الَّذِي عَلَيْهِ الْحَقُّ سَفِيهًا أَوْ ضَعِيفًا أَوْ لا يَسْتَطِيعُ أَنْ يُمِلَّ هُوَ فَلْيُمْلِلْ وَلِيُّهُ بِالْعَدْلِ) - "And if the one upon whom is the obligation is incompetent or weak or unable to dictate himself, then let his guardian dictate justly." Some scholars have even permitted a son to place his extravagant father under interdiction.

Since interdiction is a judicial ruling, it cannot be implemented except by the judgment of a Sharia judge. If something reprehensible appears in the father's mind or financial conduct, there is no harm in presenting the matter to the judge to examine his condition and rule for or against interdiction.