Investigates actual and suspected law violations, including cases of a difficult and complex nature; gathers, preserves, analyzes, and reports evidence; conducts field investigations and searches crime scenes; interviews and interrogates complainants, suspects, witnesses, and other persons to obtain information; recommends to attorneys the filing of criminal complaints; writes reports, and assists attorneys in the preparation of cases for trial; investigates the personal background of complainants, suspects, and witnesses; testifies in court regarding evidence and investigations; arrests suspected criminals. May be assigned periodically as Bureau Officer of the Day; may be assigned to investigate police officer-involved incidents, consumer and insurance fraud, hazardous materials violations, child abduction and criminal/grand jury investigations involving public officials; may be assigned to drug and other law enforcement multi-agency task forces, criminal intelligence and organized crime, and other specialized units within the Bureau of Investigation.