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Deterrence

There is a great deal of debate both here and overseas about the effectiveness of tougher sentences in both deterring criminals from repeat offences and deterring others from joining the criminal fraternity. A number of people have recently weighed in with opinions on this subject as a result of the debate triggered by Sensible Sentencing and our activities prior to the election. Some of them, such as the Governor General, appear not be particularly well informed, or they have ignored some of the research now appearing on this subject.

There is increasing evidence now that the vast majority of criminals are in fact "rational agents", that is they make more or less rational (if not moral) decisions based on the information available to them. It is true that they are often not particularly clever, but this is not necessarily the same as being rational. If it becomes widely known that a particular offence carries a far heavier penalty than previously, criminals will often modify their behaviour accordingly. Criminals react to well publicised judicial decisions and to law changes - see local evidence here. The key here is well publicised - it is important to make sure that the message gets through, another aspect of deterrence, as in this US report.

Still further evidence that criminals are rational decision makers, weighing up factors such as sentences and the chances of capture, come from this Australian report Crime, Punishment and Deterrence in Australia, A further empirical investigation from the International Journal of Social Economics. This is a pdf document that requires Acrobat Reader. Here are the conclusions they drew from the extensive study;

The economic theory of criminal behaviour posits that the decision on the part of the potential criminal whether to participate in illegitimate activities represents the outcome of a rational consideration of the benefits and costs of alternative forms of action......

and...

The results of the analysis offer significant support for a number of the postulates of the economic theory of crime. They represent important opposition to the continuing prevalence of simplistic sociological analysis of imprisonment and recidivism, which is often based on ad hoc theorizing and limited empirical validation (see Diiulio (1996) for a discussion). The significance of the clearance rate (CLR), a measure of the probability of punishment, suggests a significant negative, deterrent effect for all crime categories considered. The significance of expected sentence length (ESEN) also supports a significant negative deterrent effect for the crimes of robbery, motor vehicle theft and fraud. An increase in both the probability of punishment and the severity of punishment appears to have a significant negative impact on crime, at least for the categories of property crime examined here.

The evidence shows that most offenders can be deterred to one degree or another. It would be foolish to claim that any sentencing strategy will have a 100% deterrent effect on 100% of offenders all of the time, but then it would be equally foolish to claim that no offender is ever deterred by any sentence however tough. The truth lies somewhere between, and will vary from offender to offender. If the only value in tougher sentences was deterrent effect, than it could possibly be argued that the value of the deterrent effect is insufficient to justify the extra cost of prisons etc. However, given that we know that incapacitation, i.e. locking violent offenders up to prevent reoffending, is more cost effective than releasing them, then the deterrent effect thus also gained is a bonus, and as the evidence shows, not an insignificant one.

It is true that there are some people who we cannot deter, as they are irrational - "loose units" in the vernacular.... These however are the very people however that it is most important to protect the public from. With those whom we can deter, we should endeavour to do so, and those we cannot we need to lock up for the protection of the rest of us. It is also true that murderers may actually somewhat less likely to be deterred by heavy sentences than other types of offenders, but then again deterrence is not the primary reason for tougher sentencing anyway. Prevention is, by means of incapacitation, and if there is any crime we want to minimise the chance of recurrence for its murder...

There are three components of deterrence within a justice system, and sentencing is only one of these. The other two are detection, i.e. the likelihood of being caught, and conviction, i.e. the likelihood the having been caught, that the case will then lead to a successful conviction. We are not doing all that well on any of these components at present, particularly for violent crimes other than murder, although our rate of detection tends to improve markedly for more serious crimes. The implications of this are that for deterrence to work, all three components must be present, and so saying that tougher sentences do not deter is meaningless if there is a low probability that offenders will even be caught and convicted in the first place, as in many third world and a few Western countries or states. If any three of these components are absent or at low levels, then the levels of either of the other two components will have little deterrent effect.

The current underfunding of our police force, and their misapplication for low priority tasks such as speed camera work, along with their poor morale, results in the deterrent effect of what tougher sentencing there has been recently being undermined. Offenders know that although they might be more likely to get a longer sentence, they are less likely to be caught or convicted as the police are too thinly stretched to catch them, and too underresourced to be able to always find all the evidence and collate it in such a way that they will be likely to be convicted. Laws that allow plenty of loopholes, such as those for young offenders, do not help either.

Another factor that needs to be considered when considering the deterrent effect of sentencing, is that small, incremental changes in sentencing are unlikely to have any deterrent effect. This is partly because incremental increases such as those we have had here in New Zealand recently do not get widespread media coverage, so therefore offenders tend not to be made aware of them. But the main reason is that such incremental changes have no significant impact on the crude (but rational) decision making processes of violent offenders. It takes significant and large scale changes, such as those of the courageous sentencing decision handed down by Sydney District Court Judge Michael Finnane recently, to impact the decision making processes of the criminal subculture.

Below is a quote from a report from the Australian Institute of Criminology.

"Prison and long sentences were seen by many offenders as the two major disadvantages of robbery. Some offenders, including those who may be under the influence of drugs and those who may have become `spontaneously' involved in robberies, do not appear to spend much time weighing up the risks and rewards of robbery before making the choice to go ahead. On the other hand, there are those who do think about the possibility of being caught and the sentence. The sentence may deter some - but by no means all - of them. Over half said they knew the length of sentences for robbery, and most appeared to believe that they would think about this before committing another robbery. "

Further evidence emerges from a piece of a very worthwhile article on self defence for women , which rather contradicts the widely held theory that heavier sentences have no deterrent effect.

"He and the others in this group interviewed a bunch of rapists and date rapists in prison on what they look for and here's some interesting facts:"

"Only 2% said they carried weapons because rape carries a 3-5 year sentence but rape with a weapon is 15-20 years."

One can only assume from this that these criminals did in fact weigh up such factors as likely sentences before setting out to commit crimes such as rape. Although not all offenders are so rational, this is an indication that a substantial proportion are, and take likely sentences for a crime into account in their decision making process.

Still further evidence emerges from no less a source than the United Nations Globqal Report on Crime and Justice on page 64;

"Arab states generally reported very low rates for nearly all types of crime."

Whatever else one may think of Sharia Law its harshness certainly appears to be wielding a deterrent effect where it is enforced! We have no desire to see NZ go to these extremes, but it does demonstrate that tougher sentencing does indeed have deterrent effect.

It is interesting to look at this data from the United States. This graph of prison numbers from 1985 to 2000 and this one showing the violent crime rate 1975-2000 along with this one showing the juvenile crime rate 1970-1999 are instructive to compare, particularly over the 1985-2000 period. This graph, rates of victimisation for violent crime 1973-2000 shows that increased rates of imprisonment are having an effect on violent crime rates.

The failure of the death sentence in Texas to reduce violent crime there is often cited, although oddly enough it is with the most extreme offences and offenders that deterrence may actually be somewhat less effective due to the irrationality of such offenders. The death sentence may also be seen as an easy option by comparison with a life sentence in a harsh jail, thereby mitigating the deterrent effect of a death sentence. However, even with the death sentence, it appears the critics may actually have got it wrong, according to the evidence that emerges from the following study

In 1985, a study was published by economist Stephen K. Layson at the University of North Carolina that showed that every execution of a murderer deters, on average, 18 murders. The study also showed that raising the number of death sentences by one percent would prevent 105 murders. However, only 38 percent of all murder cases result in a death sentence, and of those, only 0.1 percent are actually executed.

On occasion, circumstances have led to meaningful statistical evaluations of the death penalty's deterrent effect. In Utah, for example, there have been five executions since the Supreme Court allowed executions to resume in 1976:

Gary Gilmore faced a firing squad at the Utah State Prison on January 17, 1977. There had been 55 murders in that state during 1976. During 1977, in the wake of the Gilmore execution, there were 44 murders, a 20 percent decrease. A decade later, on August 28, 1987, Pierre Dale Shelby, who in 1974 forced five people to drink liquid drain cleaner, kicked a ball-point pen into the ear of one, then killed three, was executed. The count for January through August was 38 murders, a monthly average of 4.75. In the aftermath of the Shelby execution, there were 16 through the months of September to December, a monthly average of 4.0.

Arthur Gary Bishop, who sodomized and killed a number of young boys, was executed on June 10, 1988. For all of 1988, there were 47 murders. During January-June, there were 26; for July-December, the tally was 21, a 19 percent difference.

During the temporary suspension on capital punishment from 1972-1976, researchers gathered murder statistics across the country. Researcher Karl Spence of Texas A+M University came up with these statistics, in 1960, there were 56 executions in the USA and 9,140 murders. By 1964, when there were only 15 executions, the number of murders had risen to 9,250. In 1969, there were no executions and 14,590 murders, and 1975, after six more years without executions, 20,510 murders occurred. So the number of murders grew as the number of executions shrank. Spence said:

"While some [death penalty] abolitionists try to face down the results of their disastrous experiment and still argue to the contrary, the...[data] concludes that a substantial deterrent effect has been observed...In six months, more Americans are murdered than have killed by execution in this entire century...Until we begin to fight crime in earnest [by using the death penalty], every person who dies at a criminal's hands is a victim of our inaction."

And more recently, there have been 56 executions in the USA in 1995, more in one year since executions resumed in 1976, and there has been a 12 percent drop in the murder rate nationwide.

And JFA (Justice for All) reports that in Texas, the highest murder rate in Houston (Harris County) occurred in 1981 with 701 murders. Since Texas reinstated the death penalty in 1982, Harris County has executed more murderers than any other city or state in the union and has seen the greatest reduction in murder from 701 in 1982 down to 261 in 1996 - a 63% reduction, representing a 270% differential!

Also, in the 1920s and 30s, Death penalty advocates were known to refer to England as a means of proving capital punishment's deterrent effect. Back then, at least 120 murderers were executed every year in the US and sometimes the number reached 200. Even then, England used the death penalty far more consistently than we did and their overall murder rate was smaller than any one of our major cities at the time. Now, since England abolished capital punishment about thirty years ago, the murder rate has subsequently doubled there and 75 English citizens have been murdered by released killers!

The Honorable B. Rey Shauer, Justice of the Supreme Court of California, has said:

"That the ever present potentiality in California of the death penalty, for murder in the commission of armed robbery, each year saves the lives of scores, if not hundreds of victims of such crimes, I cannot think, reasonably be doubted by any judge who has had substantial experience at the trial court level with the handling of such persons. I know that during my own trial court experience...included some four to five years (1930-1934) in a department of the superior court exclusively engaged in handling felony cases, I repeatedly heard from the lips of robbers...substantially the same story: 'I used a toy gun [or a simulated gun or a gun in which the firing pin or hammer had been extracted or damaged] because I didn't want my neck stretched.' (The penalty, at the time referred to, was hanging.)"

What's more, in my state of New York, the death penalty is now in effect and there are many death penalty cases in progress, and the murder rate continues to drop faster than ever.

Edward Koch, former mayor of New York City, said:

"Had the death penalty been a real possibility in the minds of...murderers, they might well have stayed their hand. They might have shown moral awareness before their victims died...Consider the tragic death of Rosa Velez, who happened to be home when a man named Luis Vera burglarized her apartment in Brooklyn. "Yeah, I shot her," Vera admitted. "...and I knew I wouldn't go to the chair."

The following links provide further supporting evidence...

Sentence Enhancements Reduce Crime a short article on the effects of one particular tougher sentencing Law in California.

An abstract of a paper demonstrating a dynamic deterrence effect where future employment prospects are affected. The paper itself may be purchased online.

A short report from the National Centre for Policy Analysis in 1997, with a number of references.

A long report from the same source in 1998, with screeds of references. This one is several pages long, but well worth the time.

An Exchange on Crime and Punishment a online debate of this issue.

This article is by Peter Jenkins. If you wish to use it in your own work, go right ahead. Some acknowledgement of the source i.e. Sensible Sentencing Trust would be appreciated.