Final answer:
Roll call Sergeants should report for duty 15 minutes before their scheduled time as it ensures preparedness for their shift and is consistent with professional standards in law enforcement.
Step-by-step explanation:
When considering the appropriate time for a Roll call Sergeant to report for duty, the best practice would be to arrive 15 minutes before the scheduled time. This allows the sergeant to be adequately prepared and ensures a smooth transition from off-duty to on-duty status. It is a common standard in law enforcement and the military to show up on time, which can typically be interpreted as slightly early, to be ready for any briefings or preparatory tasks. However, for specific guidelines, it is essential to refer to the protocol of the particular organization or department.