Analysis
NAICS 922 is the 2022 subsector for justice, public order, and safety activities, part of 92 (Public Administration).
It has only one more detailed code, 9221, which covers exactly the same activities; the definition, index entries and statistics are on that page.
County Business Patterns excludes public administration, so there is no establishment count for it.
Official definition
The Justice, Public Order, and Safety Activities subsector groups government establishments engaged in the administration of justice, public order, and safety programs.
Source: US Census Bureau, NAICS 2022 Manual.