Actuarials generally: verdict

  1. None are really up to the task. Wollert’s (2006) blunt verdict on them all as “useless” except with the youngest groups of adults is supported by the work of other researchers, such as Barbaree, Blanchard and Langton (2003).
  2. All try to predict over too long a period, and long term prediction simply doesn’t work: it might be better to concentrate on 2-5 yrs.
  3. All widely over-applied: they should only be used on people similar to the original sample.
  4. They all mix different offender types too much: incest is very different from serial rape, for example.
  5. As for age, not one of them takes this sufficiently into account. They are widely applied to older offenders, despite abundant evidence now that recidivism rates in this group are far lower than previously realised.
  6. They are indiscriminately applied to all types of prisoner, including lifers, although none of them has been standardised on this group. Lifers are different from other prisoners in many ways, not just in terms of sentence length.