The Georgia Bureau of Investigation (GBI) is the state bureau of investigation of the U.S. state of Georgia. It is an independent, statewide agency that provides assistance to Georgia's criminal justice system in the areas of criminal investigations, forensic laboratory services, and computerized criminal justice information. Its headquarters is located in unincorporated DeKalb County, near Decatur and in Greater Atlanta.

DeKalb County is located in the north central portion of the U.S. state of Georgia. As of the 2020 census, the population was 764,382, making it Georgia's fourth-most populous county. Its county seat is Decatur.