A broader civil rights investigation into allegations of discriminatory traffic stops and excessive force by the Ferguson Police Department remains open, however. That investigation could lead to significant changes at the department, which is overwhelmingly white despite serving a city that is mostly black.

The state authorities concluded their investigation into Mr. Brown’s death in November and similarly recommended no charges.

There is a high legal bar for bringing federal civil rights charges, and federal investigators had for months signaled that they were unlikely to do so. The Justice Department plans to release a report explaining its decision, though it is not clear when.