Boundaries of the criminal law

The trial is the pivotal point of the process – this is where the facts are established, the law is applied and an initial decision reached. Do note that the facts are established by the evidence that is produced in court. The start of the trial is a clean sheet and it is for the prosecution and defence to lead their own witnesses, to test the credibility of the opposition by cross-examination and to argue their own interpretation of the evidence and the law. As such it is an ADVERSARIAL process, a competition between the opposing parties. The court does not have an INVESTIGATIVE role – it is not for the judge to call or examine witnesses.

The judge should know nothing about the case at the start of the trial and should act as the umpire, spelling out what evidence is admissible or inadmissible, ruling as to the interpretation of the law to be applied and to explain the issues involved to the jury who must then decide as to the facts and come to a verdict. The trial then is a forum where the interests of procedural justice are uppermost – the right of the defendant to be heard, to be represented, to advance evidence and to cross-examine. The critical issues are often ones relating to evidence – is this confession admissible evidence?

Can the jury hear the previous convictions of the accused etc. The central idea is the presumption of innocence and the right of silence – this latter enables the defendant to remain silent at the police station and not to testify at any court hearing. Such silence cannot be used against the defendant as proof of guilt. But the presumption of innocence goes further – I have talked blithely of establishing 'facts' – what, when, how something happened is difficult to establish. This is even more the case when we are seeking to establish an accused's mental state as a 'fact' – what was intended or foreseen?

Whether something happened, then, is often a matter of probabilities – we think it likely, probable, highly probable, no substantial doubt. For civil law dealing with issues of compensation between subjects, the judge decides an issue on the balance of probabilities. But this is insufficient in criminal law where the liberty and reputation of the defendant is at stake. Here the central rule is that a fact is only established when the prosecution have proved it 'beyond reasonable doubt' – the authority for this is Woolmington.

Of course the actual operation of this rule is more questionable – we are probably all familiar with a string of quashed convictions, miscarriages of justice, over the past 25 years. These are not always failures of the trial court – many of these relate to manufacturing evidence by the police through extorted confessions or other factors – the jury in the Birmingham Six were faced with confessions backed up by forensic evidence relating to handling explosives. Others are down to the failures of the Home Office in ignoring compelling subsequent evidence – the later analysis of the DNA showed that Stefan Gisko was innocent.

Others relate to the Court of Appeal's reluctance to recognise when a conviction was 'unsafe and unsatisfactory'. But often you cannot but be astounded on the sheer insubstantiality of the evidence on which a defendant has been convicted – Silcott in the Broadwater Farm trial was not connected to the killing by any forensic evidence, any of the thousands of photos and videos at the scene, any eyewitness and was convicted on the strength of an unsigned statement saying 'you can't pin this on me, no-one will talk.

' How often in many minor cases is the requirement of proof beyond reasonable doubt ignored. After the trial and conviction, we come to sentencing and punishment – this of course raises all the questions about the formal and social functions of a penal law but it is outside the ambit of this course. Instead we turn our attention to what harms require state intervention on such a massive scale and are deserving of punishment? Can we accurately delineate the proper boundaries of the criminal law?