The G20 demonstrations in 2009 raised a number of emotive issues concerning the use of force by officers. But how might the occurrence of incidents like these be minimised?

There can be no justification for any force used against an innocent bystander, though the picture may be complicated. There may have been an attack on the officer but only the tail end of the encounter, where the officer has hit the person, is seen, for example.

Uncontrolled aggression on the part of the officer could be better dealt with by understanding ‘emotional contagion’, and using psychological profiling in police training.

Emotional contagion is perhaps best defined as the way the emotions of one or more people can infect others, serving as a stimulus for replicating that emotional response. Without proper training and awareness of emotional contagion, officers may not be aware of the way in which influences are affecting them, resulting in an aggressive emotional response to a passive situation. Police officers should at least be made aware of the potential effects of emotional contagion and how to deal with them. This type of instruction is a powerful way to reduce many of the allegations of police violence.

But there is another factor to consider in reducing the number of violent police/citizen encounters – psychological profiling. Police forces in Britain use psychometric testing, part of which is done using role-play. The role-play exercises help evaluate the potential to deal with people and situations, how information is processed and dealt with, and an evaluation of communication skills. But this is not the same as psychological profiling.

Profiling could help identify potential problem recruits. For example, during one training course I was told about, a police recruit became aggressive and confrontational with a sergeant playing the role of a difficult citizen. He did not like the sergeant’s attitude and pinned him against a wall. Later, in a role-play in which a person playing a drunk kept knocking the recruit’s helmet off, the recruit lost control and became violent, pinning the ‘drunk’ against the wall, and had to be separated and dragged off by the sergeant. This recruit completed the course and became a police officer.

Psychometric tests are not designed to detect deep-rooted emotional or psychological problems that are suppressed and hidden within an individual’s personality. These problems often show when the individual thinks their authority is being challenged or demeaned; but the authority of being a police officer alone can bring these problems to the surface. I am not speaking here of the young recruit who can be a little irresponsible, but the apparently normal recruit who has specific problems that under pressure can manifest themselves in antisocial, paranoid, delusional or abusive ways. It would not be difficult for a competent professional to determine tests to bring these suppressed disorders to the surface before a recruit leaves training. While recruits with these types of disorder are rare, the ramifications of them becoming police officers could be catastrophic.

Even the most stable officers have personal issues, and when these conditions are amplified by dealing with serious trauma at work they can trigger emotional and erratic behaviour, leading to the release of suppressed emotions that can manifest themselves in such ways as the use of excessive force. There are early warning signs, such as changes in their policing methods and personality changes. An official programme to detect and rectify these issues with counselling may be a way to reduce allegations of police violence.

Education in emotional contagion and the use of psychological profiling is currently outside the police curriculum. I think the cost and time of such a programme would be offset by the money saved in dealing with the aftermath of what we saw during the G20 protests.

Mike Finn, is a former police officer with the Met and City of London Police, an expert witness and director of consultancy for Elite International