Behind the story: How CBS News analyzed homicide solve rates across the country

Since the begin of the pandemic, homicide rates in the U.S. have jumped at alarming rates. In almost each main metropolis, the variety of homicides after the begin of 2020 are far larger than they had been in earlier years, reversing a long time of decrease homicide rates that started in the early 2000s.  

The investigative workforce at CBS News wished to grasp how police had been addressing this almost unprecedented spike in murders — and why many had been going unsolved. The workforce, together with the CBS Innovation Lab, analyzed information from main cities across the country and located declining homicide clearance rates in addition to huge disparities relying on the race of the sufferer. 

What is a “clearance rate?” 

Clearance rates are a device utilized by legislation enforcement and researchers to measure how properly a police company can solve circumstances. They’re calculated by dividing the variety of incidents that had been “cleared” or solved every year by the variety of murders that occurred in that very same 12 months. It would not matter if the murders cleared had been dedicated that very same 12 months, or 10 years prior — they’re counted in the 12 months that they are cleared.  

Why not simply use arrest rates? 

Clearance rates are completely different from arrest rates. A case might be cleared if an individual is arrested — that is the most typical cause a case is cleared — however can be cleared underneath different circumstances.  

According to FBI tips, circumstances might be cleared underneath one thing known as “exceptional” circumstances. These so-called “exceptional clearances” embrace circumstances closed as a result of the offender is lifeless, serving a sentence on one other case, if the sufferer refuses to cooperate, or in a handful of different much less frequent circumstances equivalent to if the offender is in a jurisdiction that refuses extradition, in response to Thomas Hargrove, who runs the Murder Accountability Project, which tracks unsolved murders nationwide.  

The FBI information, nonetheless, would not distinguish between circumstances cleared by arrest or by distinctive means, and it is the solely technique to get constant information for all legislation enforcement in the country.  

Why solely use 2020?  

The FBI is gradual to launch information, and, at the time this evaluation was performed, the most up-to-date information launch was for 2020.  

The information 

CBS News used two units of FBI information for this undertaking: the “Return A” recordsdata from its Uniform Crime Reporting (UCR) program, and Supplemental Homicide Report information. Both maintain information associated to homicides reported to the FBI by hundreds of police businesses nationwide.  

The information is revealed by the FBI in an archaic format initially utilized in the Nineteen Sixties, so it first needed to be extracted and remodeled by translating information manuals the FBI publishes into laptop code.  

CBS News analyzed that information, then despatched that evaluation to 14 of its stations across the country. The journalists in these native newsrooms used that information to tell their very own reporting, uncovering particular person tales of unsolved murders and households left looking for justice, whereas the nationwide investigative workforce did its personal investigative work to inform the story of a country whose legislation enforcement had been struggling to maintain up with the rise in homicides — and whose communities had been paying the price of unsolved murders. 

Want to study extra about CBS News’ methodology? We’ve revealed our code here for these . 

The information recordsdata used to calculate clearance rates did not include race information, nonetheless, and CBS News wished to analyze how the circumstances of victims of various races and ethnicities had been being solved. CBS News used the FBI’s Supplemental Homicide Report information, which accommodates detailed information on homicide victims and offenders, to reply these questions. 

That information would not instantly point out whether or not a case was cleared, nonetheless, so CBS News had to make use of the presence of offender demographic information to find out whether or not a case was solved. If there was demographic information current for the offender for a given incident, CBS News thought-about the case cleared, and if not, we thought-about it open.  

This strategy has some downsides: specifically that some businesses, in response to analysis by the Murder Accountability Project, submit offender demographic information to the FBI even when an individual hasn’t been arrested and the case is not cleared, equivalent to when a witness described the offender, however police have not made an arrest. This strategy can result in clearance rates which can be larger than what the UCR information suggests however is the solely technique to measure clearance by demographics with out requesting information from every particular person company in the country.