If you google “individual offense rates”, you’re going to get a lot of basketball statistics. But the phrase is used in Thinking About Crime, a book I’ve been reading in order to educate myself on criminology. It’s funny that no formal information about criminology is given to prosecutors in my office. More time is spent on learning the elements of a crime and practicing trial skills. Prosecutors are key actors in the criminal justice system, wielding the massive, grinding power of state coercion, faced everywhere with choices that affect years of people’s lives. This system is studied in detail by academics, economists, statisticians, and others. But we make our choices with little to no knowledge of criminology, instead relying on our gut feeling, what we have heard from others, rules of thumb, and other unreliable sources. Judges are the same.
The primary penalty that felony prosecutors impose is state prison. It is the archetypal consequence for crime. We send felons there as retribution, to incapacitate them, and for deterrence to other criminals. Retribution seems to many like a fancy way of saying “legitimate revenge.” To me, it has a dark, primal connotation. We can’t measure it with statistics. There is no number showing how many sentence per year result in appropriate retribution. Deterrence is easier to measure, but still not easy to measure. “It is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject permits.”
It’s incapacitation that jumped out at me from the pages of Thinking About Crime. Incapacitation seems capable of measurement. It is not dark and primal, like state-sponsored revenge, and it is at the heart of our current “mass incarceration” controversy. Wilson opens the subject with his typical clarity.
“To determine the amount of crime that is prevented by incarcerating a given number of offenders for a given length of time, the key estimate we must make is the number of offenses a criminal commits per year free on the street.”
(Wilson, Thinking About Crime (1975) p. 135.)
“The individual offense rate varied significantly for different kinds of offenders. For example, it was highest for larceny and lowest for aggravated assault.” (Wilson, Thinking About Crime (Rev. Ed. 1975) p. 137; citing Alfred Blumstein and Jacqueline Cohen, “Estimation of Individual Crime Rates From Arrest Records,” Journal of Criminal law and Criminology 70 (1979), p. 585.) In this study, adults who had been arrested at least twice in Washington D.C. committed between nine and 17 serious offenses per year while free. (Ibid.) “Serious” in this context means murder, aggravated assault, forcible rape, robbery, burglary, larceny, and auto theft.
The studies cited by Wilson are as old as his book, but he does have some California numbers. The Rand Group has found that the average California prisoner had committed about 14 serious crimes per year over three years of freedom. (Peterson & Braiker, Doing Crime (1980) pp. vii, 32.) The number is shockingly high. Wilson also uses California statistics to return to one of his favorite themes, that crime may be impossible to prevent. He points out that Rand also found that if no one were confined in prison, the number of armed robberies in California would be about 22% higher than it is now. (Ibid.) I think this might be a low estimate, since it does not account for the effect of deterrence: if prison were taken off the table the streets would be a consequence free environment on the streets.
Many of these statistics rely on interviews with convicts. A person serving time in California for robbery would on average admit to committing 53 robberies per year free. Burglars reported committing on average 90 burglaries per year. (Wilson, Thinking About Crime (Rev. Ed. 1975) p. 137; citing Peter W. Greenwood, Selective Incapacitation (1982) pp. 43-44.)
As I read these numbers, I was blown away by how frequently a criminal would commit crimes. I was already aware, from sources such as the National Crime Victimization Survey, that most crime goes unreported, and that the vast majority of reported crime goes unsolved. Those facts tend to imply that a lot of crime is going on out there compared to arrests and convictions. But it’s one thing to suspect that fact from the aggregate numbers. It’s another thing entirely to see what each individual is doing. Especially because I primarily deal with individuals each day: individual cases and individual victims.
Wilson’s discussion of career criminals was particularly sobering. he points out that average rate numbers are not very useful because a small number of offenders commit a very large number of offenses. The median number of burglaries committed by the inmates in the Rand study was five per year, but the 10% of inmates who were the highest-rate offenders committed on average of 232 burglaries a year. The median number of robberies was also about 5 a year, but the top 10% of offenders committed an average of 87 a year. Incarcerating one robber who was among the top 10% in offense rates would prevent more robberies than incarcerating 18 offenders who were at or below the median. (Peter W. Greenwood, Selective Incapacitation (1982) pp. 43-44, 46.)
We don’t learn much about criminology in training. But if we learned the cold hard facts about the poisonous effect that career criminals have in our communities, and the salutary effect of removing them, we might be a little more motivated to go out and get them. I read RAP sheets. I read probation reports. But reading Wilson has taught me the importance of using these things to put the full weight of the power of the state towards incapacitating career criminals.
Wilson’s numbers, and the numbers he relied upon, are old. Alex Piquero and Alfred Blumstein have newer numbers in their 2007 paper.