Turki was executed on October 17 after Asr prayers, in a shocking departure from the expected norm, in which royal lawbreakers are assumed able to dodge the consequences of their actions. No one found Turki's murderous rampage in December 2012, following a ruckus at a camp outside Riyadh in which he killed his friend and injured another person, particularly surprising; what was exceptional was that the prince did not seem to receive any special favoritism. Generally, the family will mete out discipline internally, whilst keeping the tawdriness out of the public eye as much as possible. For a royal to face public execution, with no attempt to cover-up his actions, was nearly unprecedented.
According to media, Turki spent his last hours in an emotional farewell with his family. Following custom, blood money was offered to the victim's father multiple times throughout the day, but was refused. Typically, blood money can be accepted and the convicted murderer be forgiven (murder is considered a private matter under Islam), but in this case the family failed to reach an agreement, the victim's father being inconsolable. Presumably Turki, who had been sentenced in November 2014 after pleading guilty at the trial, was beheaded, the usual method. The news was broadly welcomed among citizens, causing a social media stir. The victim's uncle, Abd al-Rahman al-Falaj, was quoted as saying that the sentence reflected the Kingdom's "fair justice system". The royals, including the king, were warmly praised for having seen the sentence carried out, despite Turki's lineage, giving a hefty dose of credence to what is often said but rarely witnessed in action - that the royal family should receive equal treatment under the law.
The last formally sanctioned royal execution took place in 1975, when Faysal bin Musa'id was put to death. He had assassinated King Faysal, angered that his older brother, Khalid, had been killed in 1966 whilst leading a demonstration against the introduction of television in the Kingdom.
Faysal's defense lawyers argued that he was unstable (and in fact he had a record of domestic violence and drug charges), but any concerns over his sanity were subordinated to the desire for retribution. The nation was in mourning for a much-loved king, and a difficult transition period under fractured leadership was underway (the new king, Khalid, was a consensus candidate, and weak; ambitious rivals were already circling). The assassin's fate was a foregone conclusion.
The most notorious example of an execution of a royal occurred in July 1977, despite not being carried out in accordance with Islamic (shariah) law. Misha'il bint Fahd, granddaughter of Muhammad, a brother of King Khalid, was killed by Muhammad himself after learning that she had run off with a young man, Muslih al-Sah'ir. Though the affair took place outside her marriage, in fact punishment for adultery is extremely rare under shariah, which requires four witnesses to the physical act itself, a very high burden of proof. Nonetheless, an enraged Muhammad carried out the execution of the couple himself, for "staining the family honor". His brothers were strongly opposed, but not for nothing was he known as Abu Sharrayn (father of twin evils, one of which was his temper).
The very notoriety of these examples highlights how unusual royal punishment can be in practice. Turki was certainly not the only prince to engage in criminality since Faysal, and even before that there are examples of royal murderers who served only house arrest as their punishment. More recently, Saud bin Abd al-Aziz was convicted in London of killing his servant, after a "sadistic" campaign of violence and sexual abuse. After a brief prison sentence there he was allowed to return home under a prison transfer arrangement. His lawyers argued that he could face the death penalty in Saudi Arabia over revelations of his homosexuality, but that has not transpired.