Presently, almost ten million people are being held in penal institutions worldwide. In the Netherlands, each day about 12.000 persons are held in Dutch prison cells, and about 35.000 persons are incarcerated each year. Imprisoning people is an expensive punishment. Each year the Dutch government spends a lot of money on incarcerating offenders. Despite the large numbers of persons experiencing imprisonment, the high costs associated with imprisonment, and its manifest importance in crime prevention, there is surprisingly little knowledge regarding the effects of imprisonment on the further life course of offenders and their families.

We do know that many ex-prisoners experience problems in their lives after imprisonment, like health problems, financial problems, and trouble finding a job. Ex-prisoners' partners and children may experience severe problems as well. Nevertheless, we don't know to what extent such problems are influenced by the detention.

In an attempt to fill this gap in knowledge, a team of multi-disciplinary scholars from different organizations have joint efforts and resources, and developed the Prison Project.

The Prison Project is a longitudinal nationwide study in the Netherlands on the effects of imprisonment. The project has the following overall aims:

1.    To examine in the conditions of confinement and how prisoners experience
        imprisonment in the Netherlands.
2.    To examine the effects of imprisonment on the following life domains:
a.    Prisoners' social economic status
b.    Prisoners' marriage/divorce chances
c.    Prisoners' health
d.    Prisoners' social networks
e.    Wellbeing of prisoners' partners
f.    Wellbeing of prisoners' children
3.    To examine the effects of imprisonment on prisoners' future criminal behavior
4.    To explore intermediate factors that may explain any effect of imprisonment

In the Prison Project, a representative sample of about 1,900 prisoners was followed for four years and interviewed at several moments during their imprisonment, as well as six months and 24 months after their release from prison. The sample of the project consists of male prisoners aged 18-65 years, who were born in the Netherlands, and who entered one of the Dutch remand centers between October 2010 and April 2011. In the first few weeks of their pre-trial detention, employees of the Prison Project approached and informed all eligible prisoners. Participation was voluntary, and all participants signed an informed consent declaration.

The first wave of the Prison Project was conducted when the prisoners were held in pre-trial detention for about three weeks. This first measurement consisted of a structured interview and a self-administered questionnaire. In total, 2,837 of the 3,981 persons meeting the selection criteria were approached. Of them 1,904 participated in the interview (67%) and 1,748 also filled out the questionnaire. Inmates who were still in prison were questioned again 3, 9, and 18 months after their arrival in custody. Each respondent was also interviewed six months and 24 months after his release from prison.

Self-reported data were collected using structured interviews and self-administered questionnaires. Moreover, a variety of officially registered data were collected for our sample. The instruments used in the Prison Project cover multiple life domains (e.g. criminal behavior, employment, social networks, family formation and disruption, health) as well as detailed characteristics of the prison experience (e.g. prison regime, sentence length, disciplinary infractions, participation in behavioral interventions). In addition, many intermediate factors that may explain why imprisonment influences prisoners' life-course circumstances are measured (e.g. labeling, self-control, social capital, criminal attitudes, and coping style).

Some additional data collections were organized as well. Partners of the respondents filled out a questionnaire about their own lives and wellbeing and about the wellbeing of their children. In addition, some prison officers filled out questions about the prison climate on their unit. Finally, probation officers filled out a questionnaire about the probation supervision of the respondents.

Combining all these data results in a very rich dataset, which can be used to answer a variety of important research questions regarding imprisonment and the effects of imprisonment.

The Prison Project is independent of the Ministry of Justice and the DJI (Dutch Prison Services).

Click here to download the PRISON PROJECT brochure (pdf).