Ibn Jurayj (may Allah have mercy on him) said: I asked Ata (may Allah have mercy on him): Is there anything (fixed) for shaving the head? He said: I do not know. Imam al-Shafi'i (may Allah have mercy on him) said: For it there is the judge's ruling (hukumah).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الديات / 16332