--- - |2+ Research Summary The clearance rates for murder and other serious crimes have declined significantly for almost 60 years despite significant technological improvements in police investigations. The reasons for this are not well understood. We argue here for rethinking why, what, and how police investigators operate so as to repurpose their work for reducing crime. These changes include improved thinking by detectives to reduce investigative errors, increased focus on patterns of crimes, and better use of detective expertise in crime prevention. Policy Implications First, police should work to reduce investigative failures by improving investigative thinking. Second, tinkering with the administrative practices of investigative units seems unlikely to produce significant results. Third, police agencies should engage detectives in crime prevention. Finally, police agencies should connect investigations to problem solving. - 'Criminology &Public Policy, Volume 18, Issue 3, Page 601-622, August 2019. '