Mental illness & terrorismCould the Sydney siege have been predicted and prevented?
It’s the question everyone is asking — could the Sydney siege have been predicted and therefore prevented based on the past behavior of gunman Man Haron Monis. Monis’s troubled history was well known to media and the police, but can we predict if and when such a person is likely to commit any further crimes? Further, we need to be very careful about stereotyping the mentally ill as potentially “dangerous.” It is simply not the case that all people with serious mental illnesses are prone to violence. There are very specific factors that govern the complex relationship between mental illness and violence. We need to understand and prevent people from experiencing them.
Monis’s troubled history was well known to media and the police. He was on bail for being an accessory to the murder of his ex-wife, faced more than fifty sexual and indecent assault charges and had a conviction for sending abusive letters to families of deceased Australian soldiers.
The self-proclaimed Iranian cleric died last Tuesday following the police break-up of the sixteen hour siege in a Sydney cafe. Cafe manager Tori Johnson and barrister Katrina Dawson also died following the gun battle.
What happened in this case will be the subject of much investigation but Prime Minister Tony Abbott says Australians have a right to ask why Monis was “entirely at large in the community,” with New South Wales Premier Mike Baird adding: “We are all outraged that this guy was on the street.”
Similar questions are asked following other cases were crimes are committed by someone known to police with a history of bad behavior, violence or abuse.
But can we predict if and when such a person is likely to commit any further crimes?
Experts and predictions
In many areas of life we rely upon experts to make predictions and decisions based on those predictions — which is often referred to as clinical prediction.
A psychiatrist might be asked to predict the chances that an offender will re-offend if released into the community. This information might be used at a parole hearing.
But for a very long time, there have been attempts to supplement and indeed replace this process with actuarial prediction, based purely on data and statistical analysis.
An example comes from the early work of U.S. sociologist Ernest Watson Burgess who in 1928 proposed twelve factors to be used in predicting parole violations, including type of offence, parental and marital status, criminal type, social type, community factors, statement of trial judge and prosecuting attorney, previous criminal record among other factors. This was one of the first efforts to use data to predict parole violations.