The Operations Section Chief is responsible for establishing tactics for the assigned operational period. The Incident Commander (IC) and any Planning Chief will determine the overall objectives and priorities and will coordinate the Incident Action Plan with the Operations Chief, among others.
ADDED: In terms of law enforcement activity - the ranking on-scene commander.
In the NIMS Incident Command System the tactics for the incident are developed by the Operations Section Chief.
operations section chief
That responsibility falls on the Incident Commander (IC).
incident commander
The Incident Commander
Incident Commander
Incident Commander
Incident Commander
Incident Commander
Incident Commander
Incident commander
Incident Commander