The young 16-year-old left the house without telling her father. As she reached home, the devout father "started thrashing her, hitting her head and body with a cricket bat and an iron rod." A manual of Islamic law certified as a reliable guide to Sunni orthodoxy by Al-Azhar University, the most respected authority in Sunni Islam, says that "retaliation is obligatory against anyone who kills a human being purely intentionally and without right." However, "not subject to retaliation" is "a father or mother (or their fathers or mothers) for killing their offspring, or offspring's offspring." ('Umdat al-Salik o1.1-2). In other...