A statistical method developed to estimate animal populations is helping to document human-rights abuses.
The latest use of multiple-systems estimation (MSE) has revealed that twice as many people died during Peru's civil war as had been thought. It works by comparing numerous partial lists, on the principle that the chance of a person appearing on two lists is equal to the product of their chances of appearing on each list separately.
MSE has previously revealed the Guatemalan army's genocidal attacks on their country's Mayan people, and confirmed the Yugolsav army's responsibility for thousands of Albanian deaths in Kosovo.
Reference: Nature 425, 6 (2003)