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More autonomy and contact with the outside world reduce aggression in prisoners

Published: 09th January 2020 Last updated: 24th January 2020

A few daily routine adjustments in correctional facilities can substantially reduce aggressive behavior in prisoners. The adjustments concern increased autonomy and more opportunities to engage with the outside world. As compared to prisoners in the standard regime, those in the alternative regime are 60% less aggressive. This is one of the main outcomes of an evaluation of an experiment with an alternative detention regime that was conducted in the Nieuwegein correctional facility by Ben Vollaard (Tilburg University), Marike Knoef (Leiden University), and Tom van Dijk, independent consultant.


This is the very first time a change in detention regime in the Netherlands has been evaluated experimentally. Designed to be suitable for national roll-out, the alternative regime was tested on a non-selective group of prisoners, with one wing of the correctional facility following the new regime and an identical, completely separate wing adhering to the standard regime. The research data concerns over 1,000 prisoners who for a period of almost two years were randomly placed in one of the two wings. The new regime was implemented halfway through this period. Random placement ensured that the alternative regime prisoners could be compared to the standard regime prisoners. The effect of the alternative regime was deduced by comparing the behavioral development in both groups of prisoners.

Poisoned living conditions: a lose-lose game

The idea behind the alternative regime is that when prisoners’ autonomy is too restricted (when to get up, where to go, what to eat, etc.) and when their isolation is too severe, they will become aggressive. A strict regime may appear an effective way of keeping prisoners on a tight rein, but the end result is more rather than less undesirable behavior. And this is in nobody’s interest: staff’s working conditions deteriorate, punishment unintendedly becomes more severe – the penalty proper is deprivation of liberty, suffering abuse during detention clearly is not – and adverse behavioral effects may linger after release. Previous pilot studies indicated the relevance of living conditions to prisoners’ behavior, but so far there had not been firm evidence for non-selective group of prisoners. This experiment fills the gap.

Increased autonomy

Alternative regime prisoners are expected to act on their own initiative more often and must therefore also more actively consider what to do when. For example, they must prepare their own meals and order groceries. They are also given passes to go to work and the gym on their own, and they are given the responsibility to lock their own cell doors when they leave their cells to take part in recreational activities.

Improved contact with the outside world

Alternative regime prisoners had improved opportunities to engage with contacts in the outside world: a telephone in their cells and a welcoming visiting hall. At their own expense and excepting blocked numbers, prisoners may use their in-cell telephones to make private calls between 6 am and 10 pm. And from being a stark space where prisoners and their visitors were separated by a long table, the visiting hall now has a pleasant atmosphere and offers more private seating arrangements that allow prisoners to have more direct contact with visitors.

Less aggression

The regime adjustments reduced the number of aggressive incidents involving prisoners, as registered by staff, by 60%. The results of the experiment indicate that the effect of repeating these regime adjustments may be both greater and smaller. A weekly survey amongst staff on the mood of the prisoners confirms that, as compared to the standard regime wing, agitation in the alternative regime wing had subsided considerably. Two other instruments gauging aggressive behavior – victimization surveys amongst staff and prisoners – also point to aggression being reduced by tens of per cents.

Revamping the visiting hall did not lead to more drugs and other contraband goods being smuggled in. This had been a concern when the regime adjustments were implemented, but it would appear to be unfounded: the researchers did not see clear effects on the prisoners’ health.

Note to editors

For more information please contact Ben Vollaard, telephone +31 6 41 60 4444, e-mail, or the press office, e-mail, telephone + 31 13 466 4000.

Klik hier voor het eindrapport: 'Het effect van een alternatief detentieregime op gedrag en gezondheid van gedetineerden'