The Effects of Imprisonment: Specific Deterrence and Collateral Effects

Compiled from Criminological Highlights by Anthony N. Doob (University of Toronto), Cheryl Marie Webster (University of Ottawa), Rosemary Gartner (University of Toronto)

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Table of contents:

  1. The effect of imprisonment on recidivism
  2. Collateral impacts of imprisonment
  3. Highlights

The effect of imprisonment on recidivism

The renewed popularity of mandatory minimum sentences makes the examination of the effects of imprisonment more important than it might have been in the past.  More generally, however, it is in the public interest to know what the impact of imprisonment is on those who experience it.

Mandatory minimum sentences almost always involve sentences of imprisonment. In some cases, people are sent to prison who – in the absence of a mandatory minimum prison sentence – would not have received a prison sentence. In other cases, the length of time that they spend in prison is longer than it would be otherwise because a mandatory minimum sentence is required.

Harsh sentences are often justified in terms of their specific deterrent impact – the presumed deterrent impact of the sentence on the offender being sentenced. The theory is simple: offenders will, because they receive harsh sentences, be deterred from committing additional offences in the future (after they have served their sentences) because they have learned that harsh penalties are the consequence of offending.

Recently, for example, the Government of Canada introduced specific deterrence (but not general deterrence) into the Youth Criminal Justice Act. This modification is based, one could assume, on their belief that Canadians would be safer if those being sentenced were given harsher sentences (or the government believes that Canadians believe that they would be safer from crime if specific deterrence was listed as a purpose of sentencing).

Implicitly, and occasionally explicitly, the Government of Canada has criticized judges for not being harsh enough. The implication of what spokespeople for the government state is clear: Canadians would be safer if judges handed down more and longer prison sentences. Said differently, judges are portrayed as being responsible for at least some crime in the community.

As it turns out, in some jurisdictions, this hypothesis – tough judges create lower recidivism rates – has been tested directly through what could be considered random assignment of those being sentenced to judges who vary in their average severity. In one study in Washington, D.C., drug felony cases were assigned to judges in what was almost a random fashion. Judges varied considerably in the average severity of the sentences they imposed. The most lenient judge sentenced about 23% of these cases to prison; the harshest judge sentenced 65% to prison. On average, the cases sentenced by the various judges were similar.  The most conservative interpretation of the findings was that the recidivism rates   of those sentenced by tough and lenient judges were the same, although there were some indications that those sentenced by tough judges were more likely to reoffend (page1 B-1) (Page numbers for the Criminological Highlights summaries (Part B of this compendium) are to be found at the bottom right. (Other numbers that might be found on some pages relate to the original source of the summary). A similar study carried out in state courts in Chicago with ordinary offenders sentenced to a variety of different offences had similar findings (Page B-2).

A large review of the findings on the impact of imprisonment on reoffending (Page B-3) suggested – especially if one focused on the highest quality research – that the impact of imprisonment was either non-existent or that imprisonment of offenders (holding other relevant factors constant) increased the likelihood that they would re-offend over the alternative – imposing a non-prison sentence.

Studies focused on more homogeneous populations show similar effects. A true (randomized) experiment in Switzerland (page B-4) demonstrated that there was no evidence of a specific deterrence effect of imprisonment in comparison with a community service. In fact, there was some evidence on some measures that prison increased the rate of recidivism. A study carried out in the Netherlands (page B-5) using a different methodology found that those sentenced to prison were more likely to re-offend than those given community service orders. Two Australian studies demonstrate the same phenomenon: imprisoned offenders are at least as likely to reoffend as those who are not sentenced to prison (page B-6).

An American study, looking at matched pairs of offenders, one of whom was imprisoned one was not, found that for both sexes, those sent to prison were, if anything, more likely to reoffend (page B-7). Another study, using a range of different methodologies and different recidivism measures found that imprisonment increases the likelihood of reoffending (page B-8). The length of time an offender spends in prison appears to be unrelated to recidivism (page B-9).

Perhaps one of the more important findings is that those sent to prison for the first time are more likely to re-offend than are equivalent offenders sentenced to a community punishment (page B-10). Similarly, drug offenders sent to prison are more likely to reoffend than those sentenced to probation (page B-11).

Part of the difficulty for those who are incarcerated is that incarceration (above and beyond being found guilty) appears to reduce a person’s likelihood of being in the workforce (page B-12).

The Canadian Youth Criminal Justice Act was designed explicitly to reduce the use of youth court and of youth custody. These strategies – avoiding formal processing of youths who have offended – appear to be sensible. A review of the data on this issue “indicates that there is no public safety benefit to [youth justice] system processing” (page B-13). Similar conclusions were reported in a recent Australian study (page B-14).

For youths, it needs to be remembered that offending rates tend to drop – even for high rate offenders – as youths age. Furthermore, long stays in juvenile facilities did not reduce reoffending (pages B-15 and B-16).

Part of the reason that harsh penalties do not appear to have much impact for youths may  be that when they are apprehended, their perceptions of the likelihood of being caught in the future do not increase very much (page B-17).

Finally, for one of the more common types of offences - drinking driving offences (In Canada, in 2010, drinking driving offences constituted the most serious charge in the case of 15.6% of those cases in which there was a finding of guilt.)  - the  size of the fine that is imposed does not matter (page B-18). Governments may wish to raise the fine for impaired driving offences (as they have done numerous times in Canada). But they should not think that by doing so anyone is made safer.

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Collateral impacts of imprisonment

When one member of a family is incarcerated, it obviously can have effects on other family members (page B-19). In fact, the incarceration of fathers increases the physical aggressiveness of their young sons (page B-20), and increases the likelihood that their sons will commit offences (page B-21). Furthermore, the incarceration of fathers increases the likelihood that their children, when they become adults, will commit offences (B-22).

Incarceration of a father can also have a negative impact on the mental health of mothers who are left to care for their child (page B-23).

The incarceration of mothers has similar negative impacts on their children – increasing the likelihood that their children will commit offences (page B-24).

Not surprisingly, the effect of incarceration of a parent depends to some extent on the role that the parent was playing before the incarceration began and the nature of the relationship between the incarcerated parent and the (remaining) caregiver, whether that person is a parent or someone else (page B-25).

Finally, the negative impact of incarceration can go beyond the immediate family and have negative impacts on the community more generally (page B-26).

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Volume 11, Number 4, September 2010: Punitive judges don’t stop crime.

Volume 13, Number 4, June 2013: Imprisonment does not reduce the likelihood of reoffending.

Volume 11, Number 1, February 2010: Incarcerating offenders who could be given non-custodial sanctions does not reduce the likelihood that they will commit further offences. In fact, incarceration may increase the probability of recidivism.

Volume 3, Number 4, October 2000: Community Service works: Those offenders given short prison sentences are, if anything, more likely to re-offend than equivalent offenders given community service.

Volume 11, Number 5, January 2011: Community Service Orders are more effective at reducing recidivism than short sentences of imprisonment.

Volume 11, Number 6, April 2011: Being sent to prison does not decrease subsequent offending.

Volume 12, Number 5, May 2012: Compared to a community sanction, imprisonment increases the likelihood of reoffending for adult offenders in Florida. This conclusion is consistent across three quite different methods of controlling for other factors and is consistent when recidivism is measured for one, two and three year follow-up periods.

Volume 12, Number 3, January 2012: The length of time an offender spends in prison on the first prison sentence has no discernible impact on the likelihood that he or she will reoffend. 

Volume 11, Number 1, February 2010: First-time imprisonment of offenders increases the likelihood that they will re-offend.

Volume 5, Number 2, October 2002: The U.S. War on Drugs and other imprisonment programs appear to ensure a continued supply of criminals. Indeed, there is “compelling evidence that offenders who are sentenced to prison have higher rates of recidivism… than do offenders placed on probation” (p. 329).

Volume 11, Number 4, September 2010: Incarcerating young adults who could be punished in the community ensures that they will be less likely to be in the workforce upon release.

Volume 11, Number 4, September 2010: Formal processing of youths in the youth justice system does not reduce subsequent offending. If anything, youths processed formally are more likely to re-offend than those screened out of the formal system or processed informally.

Volume 12, Number 5, May 2012: Youths sentenced to custody in New South Wales, Australia, were as likely to re-offend as were equivalent youths who received community-based sanctions.

Volume 12, Number 1, August 2011: A study of serious delinquents demonstrates that most serious delinquents – even high rate offenders - did not persist in their delinquent careers after being found delinquent. Furthermore long stays in prison did not reduce reoffending and for some youths appeared to increase the likelihood of future offending.

Volume 10, Number 6, December 2009: Serious juvenile offenders who are ordered to serve time in juvenile institutions are just as likely to reoffend as are comparable youths who remain in the community. Furthermore, longer stays in juvenile institutions do not reduce subsequent offending.

Volume 12, Number 3, January 2012: When youths are apprehended and arrested for offences, their perceptions of the likelihood of being caught in the future increase – but not very much.

Volume 12, Number 4, March 2012: Increasing the size of fines handed down for drinking-driving offences will not reduce re-offending.

Volume 1, Number 1, September 1997: When offenders who also are parents are incarcerated, there are predictable harms which will occur to their children.

Volume 12, Number 6, September 2012: The incarceration of fathers  leads to increased physical aggression in their 5-year old sons.

Volume 12, Number 5, May 2012: The imprisonment of parents increases the property offending of their sons.

Volume 13, Number 1, November 2012: When the fathers of children under 12 years old are imprisoned, there is an increased likelihood that these children will offend as adults.

Volume 12, Number 6, September 2012: One of the collateral effects of imprisonment is that the imprisonment of the father of a young child increases the likelihood of a major depressive episode in the mother.

Volume 9, Number 5, July 2008: The incarceration of mothers with young children contributes to crime: their children, as adults, are more likely to be involved in the criminal justice system than are children of mothers who are equally involved in crime, but who avoided being incarcerated.

Volume 13, Number 3, April 2013: Although parental incarceration is likely to have negative consequences on the prisoner’s children and those taking care of the prisoner’s children, the actual effect depends on the dynamics of the pre-existing relationships among prisoners, their families, and the caregivers.

Volume 10, Number 2, February 2009: The harmful effects of imprisoning large numbers of people from a community extend beyond those incarcerated and their immediate families: the communities themselves can show the impact of high imprisonment policies.

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