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
After a 2017 National Academy of Sciences review recommended a new statistical model, FMCSA proposed SMS changes in February 2023 (88 FR 9954) and announced enhancements on November 20, 2024 (89 FR 91874). They include reorganizing the BASICs into "compliance categories," moving Controlled Substances/Alcohol violations into Unsafe Driving, and simplifying violation severity weights to 1 or 2.
FMCSA said a follow-up Federal Register notice will announce the launch date of the enhanced SMS. Separately, FMCSA finalized changes to its Crash Preventability Determination Program in December 2024. SMS results at ai.fmcsa.dot.gov/SMS still reflect the current methodology; under the FAST Act, percentiles and alerts for property carriers are not shown publicly, but carriers can see their own by logging in.
What carriers should do
Run a quarterly CSA review. Log in to SMS at ai.fmcsa.dot.gov/SMS 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. A successful request for data review can correct the record or remove the event from the SMS calculation.