The purpose of investigating an incident is to determine if a crime has been committed and, if so, to bring to justice the person(s) who committed the crime. The investigation begins the moment the incident is reported, either by a victim or witness, or by an officer who comes upon a crime by chance. It ends with the final verdict of the court or jury.
Read the case of,
"The 380 Wobbly or Now I love her, now I don't", where luck was a factor - it usually is - but the case was solved by good teamwork.
The apartment building, a two-story structure, was anything but fancy. Not a dump, but very plain, drab even. The suspect, Levester Coley, Jr., lived on the second floor. Bersch asked one FPD officer to cover the back of the building while he took Thompson and the other FPD officer with him to Coley's door. The captain covered the front steps. Bersch told me to wait on the ground floor until he called me. That sounded more than fair to me.