Nebraska

The dog can track on or off leash. No special license is required other than a hunting license. You can not dispatch a wounded game at night; only during legal hunting hours.

State Regulations: http://www.ngpc.state.ne.us/

United States:
Canada:

Green — Tracking allowed
Red — No Tracking allowed
Gray — Tracking allowed under certain circumstances or in certain areas of the state/province, but not all