Answer:
"Field Training" is usually hosted after the Police Academy. For example if you take a look at the Los Angeles Police Department the officers in training are long sleeves with neckties. They are to be at a close watch of a T.O (Training Officer) which means that the T.O is to supervise them during a 10-95 (Traffic Stop), 10-32 (Backup Required) calls and evaluating their Code-3 (Lights and Siren) response. If there are shots fired during the course of the Field Training the Trainee is to act as a full rank officer and begin assisting and protecting him/herself and the Training Officer.