Big City Murders Rarely Random

In Baltimore, about 91% of murder victims this year had criminal records, up from 74% a decade ago, police reported. . . .

Philadelphia also has seen the number of victims with criminal pasts inch up — to 75% this year from 71% in 2005.

In Milwaukee, local leaders created the homicide commission after a spike in violence led to a 39% increase in murders in 2005. The group compiled statistics on victims' criminal histories for the first time and found that 77% of homicide victims in the past two years had an average of nearly 12 arrests.

While it was common in the past for murder victims to have criminal records, the current levels are surprising even to analysts who study homicides. . . .

In Newark, where three young friends with no apparent links to crime were executed Aug. 4, roughly 85% of victims killed in the first six months of this year had criminal records, on par with the percentage in 2005 but up from 81% last year, police statistics show.

From an August 31, 2007 story in USA Today.

In the general population about 6.5% of people have felony records and about one in fifteen has gone to prison at some point. More would have some kind of criminal record. For poor men, the percentages are much higher, although not as high as the percentages found among big city murder victims.

It is a fair guess that a disproportionate share of murders where the victim does not have a criminal record involve domestic violence or child abuse. One study from a less selective sample, reports, for example, that:

19% of family murder victims had a prior record, compared to 51% of nonfamily murder victims. Also, 56% of family murder defendants, compared to 77% of other murder defendants, had a prior record.

Family murder victims make up an minority, but important subset of murder cases:

Among murder victims 6.5% were killed by their spouses, 3.5% by their parents, 1.9% by their own children, 1.5% by their siblings, and 2.6% by some other family member.

Indeed, these numbers understate the issue, according to another study linked at the same source:

The fact that only 75% of murderers have adult crime records should not be misunderstood as implying that the remaining 25% of murderers are non-criminals. The reason over half of those 25% of murderers don't have adult records is that they are juveniles. Thus, by definition they cannot have an adult criminal record. Juvenile criminal records might well show these murderers to have extensive serious criminal records.

The hopeful side of this picture is that it might be possible to concentrate incarceration so that the highest risk felons get long sentences, while a less fear driven approach can be taken towards others who are convicted of crimes. For example, almost 90% of murderers with criminal records have criminal records that involve prior violent crimes. Recidivism is bad, but the harm caused by a typical property crimes is not so great that any degree of recidivism is intolerable.

The numbers are interesting because they say a lot, implicitly, about why murders take place and what kind of social networks are involved in killer-victim relationships. This also plays out in the geography of murder. For example, when I lived in Buffalo, a stunningly high percentage of all murders in the metropolitian area took place in the ghettos of the East Side neighborhood of Buffalo proper.