Sorry Louise Mensch, you don't get to decide how the law works

Despite the guilty verdict this week, Louise Mensch is sticking by her remarks that Thomas Mair’s trial – which resulted in his life imprisonment for the murder of Jo Cox – was potentially prejudiced. Mensch of course has a right to free speech and to her opinion. And she has raised some very interesting questions about criminal trials in general. Had it not been for her obsessiveness over this particular case, people might have begun to listen.

As a former police detective who has been party to the entire criminal investigation process, and worked with the Crown Prosecution Service in bringing offenders to justice, I have no doubt that Mair has been rightly convicted for the horrendous act he committed.

Like most Britons, I wasn’t present at the trial of Mair – and neither was Mensch. Yet she has become convinced that something unusual, perhaps wrongful, took place during the justice process. What is wrong is that a beautiful wife, mother, daughter, sister and public servant was killed in her prime, in such a violent and barbaric manner.

Mensch has been critical of the media reporting of the trial, but it is the questions she has raised over the way the criminal justice system handled the defendant’s mental health that has angered many, and got my back up too.

Of course I do not know why there was no psychiatric evidence offered at court in defence of Mair – but neither does Mensch. And for that reason, she has no evidence that such events prejudiced the trial. What we do know is that, in the police interviews, Mair was given ample opportunities to speak and explain himself, and to discuss his mental health – and he didn’t. Where a defendant’s judgement is seriously impaired by mental illness, they can be found unfit to stand trial. In this case, that did not happen.

This was never going to be an ordinary legal trial. A British politician was murdered on the streets of Britain by a far-right extremist. But what right does Mensch have to question the expert conclusion of criminal justice professionals, who work with individuals like Mair every day, on the basis of media reports? In all the trials I have been involved in, the jury is told to concentrate on only the evidence that they hear in court.

Judges do sometimes get things wrong. There are recent, and troubling, cases of miscarriage of justice in this country. But there is absolutely no evidence that this sensitive trial has been prejudiced in any way, and to suggest it has – especially in this febrile climate – is not only incredulous but dangerous. What Mensch has tried to do is to muddy clear waters for personal and political gain.

In one aspect, however, Mensch is right. There are some serious questions to ask about our legal system, especially around race equality. The law doesn’t always work for everyone and we already acknowledge the Criminal Justice System to be unfair towards specific social groups. That must stop.

But, in this case, there is no suggestion that such distortions occurred. Justice was done, and prevailed. Mensch must accept this and move on.

Kevin Maxwell is a writer, advocate and former detective of both the Greater Manchester Police and London’s Metropolitan Police