Traffic Homicide Investigator

A Traffic Homicide Investigator (THI) is generally a sworn law enforcement officer who is assigned to investigate fatalities resulting from motor vehicle collisions. As opposed to an ordinary criminal investigator, whose forte is in the analysis of physical evidence such as biological, chemical, ballistic, and other types of evidence generally found in death investigations, a THI has special training and experience in traffic. A THI is usually a traffic officer who has investigated a great number of nonfatal crashes who advances toward more in-depth crash investigation. Traffic Homicide Investigators carefully document the scene of a crash, ideally in a manner thoroughly enough to reconstruct the scene at a later time, after the roadway has been reopened. This includes documenting the curvature, slope, superelevation, width, condition, and type of roadway on which the fatality occurred; seat belts, braking mechanisms, airbags, tires, and other features of vehicles; the mental state, age, experience, ability, possible intoxication or distraction, driver history, vision, reaction time, level of fatigue, and attitude of operator(s) of the vehicle(s); pavement markings, traffic signs, traffic signals, street lights, crosswalks, railroad crossings, and traffic control devices; weather conditions, lighting, fog, wetness of road, visual obstructions, and other factors; and many other elements that can affect a collision.