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GlossaryCrime reporting systems

Group B offense

A Group B offense is generally reported to NIBRS through arrest information. Learn why its counts cannot be treated as complete incident totals.

A Group B offense is a NIBRS classification generally reported through arrest information rather than the detailed incident information collected for Group A offenses. The distinction governs the national statistical submission. It does not mean that agencies cannot maintain local reports about the underlying events.

What the submission contains

The FBI's 2025.0 NIBRS manual describes a Group B Arrest Report as information about the arrest circumstances, the arrest offense, and the arrestee. It directs a separate report for each arrestee. This differs from the linked offense, victim, property, and other information in a Group A incident report. FBI NIBRS manual, section 3.2

Driving under the influence and disorderly conduct are examples within the Group B framework. Their national arrest totals do not measure every episode of the underlying conduct. An event without an arrest may exist in local call or report records without appearing as a Group B arrest submission.

The group is a statistical distinction, not a legal verdict or a universal seriousness scale. State law determines the actual offense and charge. Classification membership should also be checked against the manual for the applicable year, because reporting systems are revised over time.

Example

Hypothetical example: Officers investigate two separate reported disturbances. One results in a disorderly-conduct arrest, while the other ends without an arrest. The local dispatch system retains both service events. The NIBRS Group B arrest data include the qualifying arrest.

It would be inaccurate to call the single arrest record the total number of disturbances. It would also be inaccurate to infer that no second event occurred merely because it is absent from that arrest dataset. Each system captures a different stage and scope of activity.

Common confusion

Group B does not mean Part II in every context. SRS and NIBRS use different classification frameworks, and their categories should not be swapped without a documented mapping.

Nor does an arrest record establish conviction. NIBRS arrest reporting also has technical rules about arrest types and links to previously submitted Group A incidents. The public table's documentation determines how those records contribute to the displayed total.

Using a Group B table

Read the heading as an arrest measure unless the publication expressly defines another unit. Verify whether counts are arrest events or distinct people and whether one person can appear more than once. When comparing Group A and Group B data, state that their reporting bases differ; otherwise, apparent differences can reflect incident-versus-arrest collection rather than differences in the frequency of conduct.

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