Flawed assessment 'raising sex-attack risk'

Leggate, Stuart & MacDonald, Stuart, Timesonline (UK), July 6, 2008

The system used by Scottish police, social workers and prisons to decide 
whether offenders will strike again is unreliable, researchers claim. 

Sex offenders are being wrongly released because the system used to 
assess their risk to the public is flawed, a new report has claimed.

Researchers warn that the Risk Matrix 2000 system, used by the police, 
social workers and the Scottish Prison Service, to determine the 
likelihood of sex attackers re-offending, is unreliable and should be 
scrapped.

Risk Matrix predictions are presented to judges and sheriffs when 
offenders are sentenced and are part of the criteria on whether they 
should be considered for early release. They are used by the police to 
determine which offenders should be monitored most closely on release.

There are more than 3,500 people on the sex offenders register in 
Scotland, the majority of whom are assessed using Risk Matrix. They are 
given scores based on factors including the type of offence committed 
and who their victim was. They are categorised as at a low, medium, 
high, or very high risk of re-offending.

Psychologists at Glasgow Caledonian University, whose findings have been 
published in the British Journal of Psychiatry, say that the system's 
chances of predicting the behaviour of individuals is as low as 3%.

"It's very popular and has been pushed by the government because it's cheap, but it doesn't actually work," said Professor David Cooke, a clinical psychologist who was part of the research team. "Often offenders will be deemed to be low risk when they are actually high risk, and the opposite is true as well. The public is suffering because people who are high risk will be slipping through the net."

Stuart Leggate, who murdered eight-year-old Mark Cummings in 2004 in 
Glasgow, was considered "medium risk" at the time of the killing. 
Leggate had been released early from a prison sentence for sex attacks 
on children.

The Risk Management Authority (RMA), a government group on risk 
assessment, published a study into Risk Matrix 2000 this year, which 
found it was a viable screening tool with a moderate level of accuracy.

Roisin Hall, the authority's chief executive, said the system was used 
as a "starting point" for assessing offenders and many other factors 
were taken into consideration when determining risk status.

"We can never predict human behaviour and there's always the danger that people will be wrongly classified.

"What the RMA is saying about the pros and cons of Risk Matrix is be sensible, be proportionate about it, and take other factors into consideration," she said.