Musannaf Ibn Abi Shayba 18:181

Abu Bakr narrated to us, he said: Muhammad ibn Bakr narrated to us, from Ibn Jurayj, from Abd al-Aziz ibn Umar, that the commanders of the armies gathered before Umar ibn Abd al-Aziz regarding the throat: If it is broken and the voice is cut off from the man, the blood money is complete.