Canadian Study Finds Length of Incarceration Decreases Recidivism

Simon Fraser University in British Columbia has this press release announcing this study in the Journal of Criminal Justice regarding the effect of sentence length on recividism. Overall, studies on this issue have mixed results and generally show little effect either way, as Elizabeth Berger and I describe in this article, which is cited in the new article.

Here is the abstract:

Several theories and policies on punishment describe within-person processes whereby an increase in the number of days a person spends incarcerated decreases their likelihood of reoffending. Contradicting these perspectives, meta-analyses report universal consensus that incarceration has either a null or crime-inducing impact on reoffending. However, studies included in this meta-analytic work relied on between-group analyses. Within person analyses more closely align with how theories and policies describe the relationship between incarceration and reoffending and have the additional benefit of addressing the selection bias problem of between-group analyses. Using longitudinal data from the Incarcerated Serious and Violent Young Offender Study in British Columbia, Canada (n = 1719), a first-differenced fixed-effect estimator modeled the relationship  between year-over-year change in the number of days spent incarcerated and future year-over-year change in number of convictions. Between ages 12–25, year-over-year increases in days spent incarcerated prospectively influenced year-over-year decreases in  convictions. This finding was consistent across types of convictions, age-stages, ethnicity, gender, birth cohort, and exposure to different youth justice legislation. It is unclear whether reductions in convictions resulted from incarceration having a deterrent effect or a rehabilitative effect. It would be a mistake to interpret findings as support for expanding the use of incarceration or that Canada’s correctional system should maintain the status quo.

Regarding that last sentence, yes, it is a mistake to go and make policy based on one study. But that doesn’t stop ideologically driven people from doing exactly that when a single study produces a result that favors their pre-determined policy. Former Los Angeles District Attorney George Gascón did that with a “studies show” claim, citing one unpublished manuscript and ignoring the body of published literature. See our article, linked above, for details.