On corroboration

How much evidence should be needed before a person can be convicted? In systems that have a requirement of corroboration the answer is at least two. This is normally understood as a protection for the accused person, as no one can be convicted on the basis of an unsupported accusation from one other person. If this is the aim of corroboration then this seems right, but since it does not say anything about the weight or quality of evidence, the strength of the protection it provides in practice may not be clear. It would be unjust if a person could be convicted on the basis of two (or more) weak pieces of evidence; but equally if there is one really convincing witness or a strong and compelling piece of evidence it can seem rather arbitrary if a prosecution cannot proceed for want of a second piece of corroborating evidence.

These thoughts are prompted by the imminent publication of the Carloway Review in Scotland. This was an investigation established in the wake of the decision of the Supreme Court of the UK in the case of Cadder. This case held that legislation that allowed suspects to be detained by the police for up to six hours without access to legal advice was contrary to the European Convention on Human Rights - raising the unthinkable prospect that if those detained were in fact to receive legal advice then they might exercise their right to silence making convictions hard to obtain in large numbers of cases. In the light of this (and other) concerns arising from the case Lord Carloway was asked to look at what reforms might be necessary to the criminal justice system in order to ensure that it could still work effectively. And one of the possibilities canvassed was that it might be necessary to remove or relax the corroboration requirement.

It seems highly unlikely that Carloway will recommend abolition, as corroboration and the protection it is thought to offer is central to the self-image of Scottish criminal justice. But I have two observations to make here. It seems clear that the requirement of corroboration can operate as protection against certain types of accusation, but it is not clear that this protection operates across the board. Corroboration has its origins in a pre-modern system (indeed a mediaval system, most historians agree) where criminal actions were brought by private individuals. Specifically it pre-dates the establishment of modern police forces in the nineteenth century and the systematic prosecution of individuals for minor 'police' offences. In modern practice then the requirement of corroboration in many criminal prosecution means no more than that police officers work in pairs. Corroboration is less a protection than a formality. If this is the reality in minor offences, corrboration can operate in a different way in sexual offences. Here the problem is often that an accusation of rape might boil down to the word of the complainer against that of the alleged attacker, but in the absence of corroboration the case will never come before a jury. In this type of case then corroborationan is a protection, but of the wrong kind, as the high threshold might prevent justice from being done.
If this is right then there may be grounds for rethinking the place and importance of corroboration.

[Update 18th November: I'm happy to say that my prediction above was entirely wrong, as the Carloway Review has wrongfooted everyone and recommended the abolition of corroboration. This, of  course, will still have to be implemented by the Scottish Government, and there is likely to be resistance, but the gauntlet has been thrown down.]