Felony Investigative Assistance Team (FIAT) is a multi-jursdictional Police taskforce based in DuPage County Illinois. Protecting approximately 300,000 people.

DuPage County is located in the Western Suburbs of Chicago

Accident reconstruction is the process of using physical and factual evidence, in conjunction with mathematics and physics, to determine how a crash occurred.


When conducting any investigation or reconstruction, FIAT Crash Investigators use the “scientific method.” The scientific method is a process of inquiry which relies on four elements: observation, hypothesis, theory, and experiment. The underlying objective is always the same even though interaction between these four elements may differ from one situation to another.


During motor vehicle crash reconstruction, we can determine the impact speeds and directions of the vehicles involved, the time and distance relationships between the vehicles prior to the incident, and the impact severity (Delta V) relative to occupants or pedestrians.


We also attempt to find evidence relative to vehicle condition, operability of lamps and lighting, condition of brakes, tires, and other components that could play a role in a crash.


FIAT Crash Investigators use several methods of data collection and analysis, including the methods of conservation of momentum, computer simulation, photogrammetry, and component or full scale crash testing.