One of the most critical errors police supervisors can make during a major case investigation is to move too quickly. Rather, the pace of an investigation should be controlled. The early phases are usually the most important and personnel-intensive. Almost simultaneously, police personnel should process crime scene information, interview victims, pursue initial leads, and canvass residents and motorists for additional leads. Police supervisors should harness the abilities of police patrol officers in the early phases of an investigation to perform specific tasks and should seek the assistance of surrounding law enforcement agencies. Just as investigators use checklists to guide them in processing crime scenes and documenting investigative steps, police supervisors should use a checklist as a guide while performing supervisory duties. The focus of an investigation should be on the evidence and the crime scene, and police supervisors should ensure investigators have sufficient evidence to convict a suspect before the individual is detained. In addition, police supervisors should keep their superiors informed of vital case details and should let the prosecutor know when a major investigation is initiated. In many cases, investigators require the assistance of prosecutors in preparing search warrants and other legal documents. Finally, police supervisors should cooperate with the media, monitor the welfare of subordinates, control case investigation files, and keep investigations focused. 2 photographs