CSA (Compliance, Safety, Accountability) is a safety compliance and enforcement program managed by the FMCSA (Federal Motor Carrier Safety Administration) for both motor carriers and drivers. It replaced SafeStat, a former data-driven analysis system that assessed the safety status of individual motor carriers. CSA introduced the SMS (Safety Measurement System), which plays a crucial role in evaluating and addressing safety issues within the industry.

The SMS assesses carriers' safety performance by considering various factors over 24 months. These factors include roadside inspections, investigation results, and crash data. The FMCSA updates the SMS monthly, making the safety data available through the FMCSA's Safety Measurement System online.

The SMS takes into account the number of safety violations and inspections, the severity of violations or crashes, when these events occurred (with recent events weighted more heavily), the size of the carrier's fleet, the total vehicle miles traveled, and the identification of Acute and Critical Violations uncovered during investigations. This comprehensive data is used to prioritize carriers with safety concerns for interventions, such as warning letters and investigations.

It's important to note that CSA scores not only impact carriers but also have implications for drivers. These scores influence a driver's safety record and their performance while operating under a motor carrier, even including owner-operators.

The FMCSA organizes SMS safety data into seven categories known as BASICs (Behavior Analysis and Safety Improvement Categories). Within each BASIC, carriers are grouped with others that have a similar number of safety events, such as crashes, inspections, or violations. Carriers are then ranked and assigned a percentile from 0 to 100, with higher percentiles indicating worse performance. This ranking system is used to prioritize carriers for intervention strategies and compliance actions.