Multidisciplinary Accident Investigation Teams (MAIT)

The California Highway Patrol's (CHP) Multidisciplinary Accident Investigation Team (MAIT) Program was established in 1978. The severity and intricacy of traffic collisions dictated the need for more intensive investigations to determine subtle collision and injury causes.  The objective of the MAIT Program is to provide the CHP with the means to conduct in-depth investigations and analyses of major traffic collisions throughout the state.  Investigations include the reconstruction of an incident and a study of the factors that may have contributed to the incident.  The factors include environmental, human and mechanical and are associated with the three phases of a collision which are pre-collision, at-collision and post-collision.  The ultimate objective of the program is the utilization of these identified causation factors to prevent collisions of a similar nature from recurring.

​The current MAIT Program consists of teams based in the following CHP Division offices: Northern Division (Redding), Valley Division (Sacramento), Golden Gate Division (Vallejo), Central Division (Fresno), Southern Division (Los Angeles), Coastal Division (San Luis Obispo), Border Division (San Diego), and Inland Division (San Bernardino). Each team consists of investigators with specialized training in traffic collision reconstruction. The MAITs are composed of one CHP sergeant (the team leader), two or more CHP officers, one Motor Carrier Specialist I (MCS I), and one Senior Transportation Engineer from California Department of Transportation (Caltrans).

MAIT investigation
  • ​The MAIT team leader determines the scope and direction of each investigation and coordinates team efforts. The MAIT officers are trained in the physics of collision analysis and reconstruction, occupant kinematics (human factor analysis), vehicle dynamics (collision damage analysis), scene photography, the use of surveying equipment, and Computer-Aided Design software. Officers also conduct detailed interviews and interrogations and assist the MCS I with mechanical inspections. In addition to the officers assigned directly to the team, MAIT associates are used whenever possible. Associates are qualified officers assigned to CHP Area offices and are available to the MAIT Program on an on-call basis. The MCS I is responsible for conducting in-depth mechanical inspections of involved vehicles and for the completion of related reports.

  • Caltrans Senior Transportation Engineers have educational and technical knowledge which allows them to conduct in-depth investigations into the environmental factors and roadway conditions at the incident scene.

​The two categories of MAIT investigations include full and limited. In a full investigation, the team handles all aspects of a traffic collision investigation and their report is the original report. During a limited investigation, the team handles a specific aspect of a traffic collision and their report is a supplemental to an original report. The case workload is dictated by not only the number of requests from the CHP and allied agencies, but also the complexity and level of each investigation. The MAIT investigations can include, but are not limited to, information such as:

  • ​Roadway Description

  • Driver Profiles

  • Autopsy and Injury Description

  • Physical Evidence Description

  • Physical Evidence Diagram

  • Physical Evidence Analysis

  • Vehicle Damage Description

  • Vehicle Damage Description

  • Mechanical Inspection

  • Velocity Calculations

  • Dynamics Diagram

  • Time-Position Analysis

  • Collision Sequence

  • Conclusions

  • Recommendations

​Other responsibilities of the MAIT Program include the support of its investigations through the criminal and civil litigation processes. Additionally, MAIT personnel are frequently called upon to provide support during the trial process by providing information regarding any phase of MAIT operations to the CHP or any other state or public entity.

​The MAITs also assist the CHP's Critical Incident Response Team and the Office of Air Operations with the documentation of physical evidence at officer involved shooting incidents and aircraft collisions. Since the program's inception, MAIT personnel have conducted over 9000 investigations.

​The expertise exemplified in each investigation by the team members has contributed to the CHP's reputation as being one of the country's leading authorities in the field of collision reconstruction despite the diversity of cases encountered. The MAIT services and resources continue to support CHP and allied agency investigations.



What is the difference between Dynamics and Kinematics?What is the difference between Dynamics and Kinematics?<p>​Dynamics: The branch of mechanics concerned with the <em>motion of bodies under the action of forces</em>. </p><p>Kinematics: The branch of mechanics concerned with the motions of objects without being concerned with the <em>forces that cause motion</em>.</p>
Why are skid marks important?Why are skid marks important?<p>​​Skid marks are important physical evidence gathered by investigators at collision scenes. For example, when brakes are applied to full wheel lock or impending wheel lock on anti-lock brake systems during a hazardous situation, tire friction marks may be left on the roadway surface. The length of these tire friction marks can often times be used to determine the estimated speed of the vehicle, at the time the tire friction mark was made. </p><p>Two factors must be considered when estimating speed from tire friction marks: 1) The distance the vehicle slid and 2) The coefficient of friction (drag factor) of the roadway surface in question.</p>


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