I still recall the moment when, as a first year undergraduate I was informed by my social science lecturer that ‘policing was not about fighting crime’.

We were nothing less than incredulous for as naïve consumers of television crime drama we had all assumed that policing was about solving crimes and bringing offenders to justice. However, it did not take us long to understand that the deployment of police resources are far more influenced by political and cultural pressures than by what actually happens to real people on the real world.

Paris Brown , the 17 year-old former Kent youth police and crime commissioner would have understood the meaning of my former social science lecturer’s discourse on the construction of crime. After she resigned for the silly comments she made on Twitter, she was interviewed under caution for her tweets. Apparently the Kent police is a time rich institution. Special Branch found the time to interview the 17 year-old about her old boastful and apparently offensive tweets. After pondering on the meaning of this teenager’s reflections on social media the Kent police concluded that on balance and in context they were not grossly offensive and therefore she would not be prosecuted.

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Paris Brown’s lawyers responded to the investigation of their client by claiming that it was ‘wholly disproportionate’ to her case. Obviously in the grand scheme of things their point is something of an understatement. However, what the police decide to investigate and turn into an issue is guided less by the objective gravity of an act than by the impression of managing perceptions and making statement.

In the current era, teenagers tweeting offensive and hurtful comments are for more likely to be investigated than petty thieves or someone committing an act of anti-social behaviour on the street. A cynic might conclude that the current preference for policing the social media over dealing with off-line anti-social violence is motivated by the aspiration to appear to be doing something. However, that’s only part of the story. Policing was and remains influenced by the imperative of managing perceptions and making a statement.

At least Paris Brown is alive and it is possible to investigate an act that can be directly attributed to her behaviour. That is far more than can be said about Operation Yewtree and its crusade against historic crimes or historical sex crimes. This Operation was launched in the wake of media revelations about Jimmy Savile’s predatory behaviour. What is remarkable about Operation Yewtree is that it is not so much in the business of solving reported crimes but is devoted to the task of discovering or constructing sex crimes allegedly committed a very long time ago.

Nor is Yewtree confining their investigation to allegations against Savile. A second strand of its operations is designed to discover sex abuse allegations against ‘Jimmy Savile and others’. And a an all-encompassing third strand of Yewtree throws its net as wide as possible by searching for accusations against people who are entirely unconnected to the Savile sex abuse investigations. According to a report by The Sun, the 83 year-old entertainer Rolf Harris was arrested under this strand of Yewtree investigation.

Whatever the rights and wrongs of the handful of arrests of elderly show-business figures by Yewtree the question worth asking is what purpose do they serve? Even the police acknowledge that the investigation of historic allegations is neither about fighting nor solving crime. Such operations are justified on the grounds that by actively soliciting allegations they give voice to the victim. In reality the main accomplishment of such an investigation is to make a moral statement and create the impression that through putting right past wrongs something positive will be achieved in the here and now. However, the crusade against historical crimes is less about exacting justice than in destroying reputations.

No system of real justice can test the merits of an allegation made about an individual act of abuse committed over 40 years ago. It can however be used to make an example and tarnish the name of the accused. The mere act of arresting someone on such a historical allegation is sufficient to call into question the moral status of such an individual.

The investment of so much energy into investigating allegations of historical crimes also raise questions about how the police spend their time. At a time when it is claimed that the police are overstretched is the investigation of teenage tweets or the search for unreported historical crimes the best use of resources? Might not the solving of reported crimes of violence be a better way of deploying the forces of law and order? Policing crime instead of impressions would be a step in the right direction.