Crime is a major problem in most societies. Especially, there has been said that soldiers are likely to become a perpetrator since PTSD in the US army was focused after Vietnam War. Also in Japan, crimes committed by a soldier in Okinawa are sometimes reported, and ignite the dispute about public safety and Japan-US alliance.
Recently, an academic article was published dealing with this issue. The researchers investigated a total of 975,057 soldiers in the US army to extract the risk factors of being a violent criminal.
Psychological Medicine: Predicting non-familial major physical violent crime perpetration in the US Army from administrative data
As a result, they found that social disadvantages, early career age, prior crime, and mental disorder treatment were relevant to subsequent offences. In men, 24 alignments including young, poor, ethnic minorities with low ranks, disciplinary trouble, a suicide attempt, and a recent demotion were likely to be predictive.
Los Angeles Times: New tool can identify soldiers most likely to commit violent crimes, study shows
These results can be utilized to identify the risk of violence in the military, to treat risky persons in a preventive way. As the article above describes, even the most dangerous group has a little risk of violence in the future. It is unfeasible to exclude them from the team.
There are many risk assessment tools established in this domain. It is not easy, however, to rely on these tools in clinical or social settings. They never tell whether a person will be a criminal at all. Also, evidence suggests that history of violence is the greatest risk of future violence in most studies. It means that people who committed a violent crime once will never be safe.
The purpose of risk assessment is to manage the risk. The military is suitable for utilization of this kind of tool as a risky and administrative environment. But it is crucial how to deal the risky people. I do not want the world like “Psycho-Pass” in which criminal tendency is evaluated by a machine and people identified as high risk are eliminated.