Pakistan, Sept. 15 -- Upholding the life sentence of a man convicted of murdering his wife in Karachi, the Supreme Court described domestic homicide as a "crime of difficult proof." Such deaths occur in spaces often controlled by the alleged perpetrator, where evidence may disappear, and murder can be presented as suicide, accident or intrusion. Investigators who approach these cases carelessly, the court said, should face consequences.

The judgment reaches far beyond one conviction.

Pakistani society places enormous moral weight on the sanctity of the home. Yet the same idea has often protected violence from scrutiny. Bruises are dismissed as marital disputes. Threats become anger. A daughter who returns home after being beaten is advi...