Scholarly study of the factors affecting homicide clearances is at the same point as scholarly study of police patrol officers more than 50 years ago. Major organizing frameworks provide contradictory images of the factors affecting homicide clearances. This study examined whether the visibility of homicide and the singular importance of homicide clearances pushed extra-legal factors to the explanatory periphery; it examined the effects of a census-tract measure of victim social class and the race composition of the census tracts where homicides occur; it examined the distinction between dunkers and whodunits; and it explored whether measures of homicide circumstances belong in models of homicide clearances. This study supported four conclusions: (1) murders in African-American neighborhoods had lower clearance rates; (2) no clear evidence supported that direct measures of extra-legal factors affected homicide clearances; (3) no support was found for arguments that detective experience and workload affected homicide clearances; and (4) evidence was found that the visibility and seriousness of homicide and the singular importance of homicide clearances combined to cause homicide detectives to work aggressively to clear all homicides regardless of where they occurred or the characteristics of homicide victims. Appendix and references