How CSA scores get computed
Compliance, Safety, Accountability (CSA) scores come from the Safety Measurement System (SMS). The SMS calculates percentile rankings across seven Behavior Analysis and Safety Improvement Categories (BASICs): Unsafe Driving, Crash Indicator, HOS Compliance, Vehicle Maintenance, Controlled Substances/Alcohol, Hazmat Compliance, and Driver Fitness.
Scores reflect a 24-month rolling window of roadside inspection data, crash data, and investigation results from the FMCSA Motor Carrier Management Information System (MCMIS). Each event is severity-weighted; recent events are time-weighted higher.
SMS Modernization status
FMCSA's SMS Modernization initiative responds to longstanding industry critique that the percentile system unfairly penalizes carriers in densely-inspected states. Recommendations from the 2024 working group included: severity weight rebalancing, denominator changes for power-units-only carriers, and clearer crash preventability handling.
Implementation is staged. Some refinements have rolled out (improved crash preventability determination process); others remain in design. Public CSA scores at csa.fmcsa.dot.gov continue to reflect the legacy algorithm.
What carriers should do
Run a quarterly CSA review. Pull your scores at csa.fmcsa.dot.gov and check each BASIC for alert flags. If you see an alert, investigate the underlying inspection events for data integrity issues - duplicate citations, mis-attributed inspections, and incorrect VIN entries are common MCMIS data errors.
Use FMCSA's DataQs system at dataqs.fmcsa.dot.gov to challenge inaccurate inspection data. Successful challenges remove the event from the SMS calculation.