Homicide archivist Thomas Hargrove now has the largest catalogue of killings in the country—751,785 murders carried out since 1976, about 27,000 more than appear in FBI files, reports The New Yorker. States are supposed to report murders to the Department of Justice, but some report inaccurately, or fail to report altogether, and Hargrove has sued some of these states to obtain their records. Using computer code he wrote, he searches for statistical anomalies among ordinary murders resulting from lovers’ triangles, gang fights, robberies, or brawls. Each year, about 5,000 people kill someone and don’t get caught, and a percentage of these men and women have killed more than once. Hargrove intends to find them with his code, which he calls a serial-killer detector.
Hargrove created the code, which operates as a simple algorithm, in 2010, when he was a reporter for the now defunct Scripps Howard news service. The algorithm forms the basis of the Murder Accountability Project, a nonprofit that consists of Hargrove, a database, a website, and a board of nine members, who include former detectives, homicide scholars, and a forensic psychiatrist. Through data aggregating, the algorithm gathers killings that are related by method, place, and time, and by the victim’s sex. It also considers whether the rate of unsolved murders in a city is notable. Statistically, a town with a serial killer in its midst looks lawless. In 2010, Hargrove noticed a pattern of murders in Lake County, Indiana, which includes Gary. Between 1980 and 2008, 15 women had been strangled. Many of the bodies had been found in vacant houses. Gary police denied a problem. Eventually, Hargrove heard from a deputy coroner, who had also started to suspect that there was a serial killer in Gary.