The Scottish Law Commission has submitted a report which suggests that a fundamental principle of Scots Law is illogical and incoherent, and that it should be changed.
The principle being challenged is that the prosecution cannot use previous convictions to help prove their case against an accused person.
It is based on the belief that in order to ensure that the accused is given a fair trial, his innocence must be presumed until it can be proven otherwise. And the proof must be based on the specific facts of the specific offence.
However English Law differs from Scots Law in that it does permit the use of previous convictions as important explanatory evidence. The case of Peter Tobin has been cited in support of this change:
When Peter Tobin was on trial in England for the murder of Dinah McNicol, the jury were told that Tobin had been convicted for murdering Vicky Hamilton and this fact had been used as evidence to establish his behaviour patterns.
In Scots Law, this would not have been permissible evidence, despite the fact that it helped secure Tobin’s conviction in England. In some quarters, the feeling is that Scots Law needs to change to ensure that its laws are not preventing convictions that otherwise would have been made.
It is argued that how the accused behaved in the past can be relevant to whether he behaved in a similar way in relation to the offence with which he is charged today. In an important sense, this is correct.
People do naturally fall into particular patterns of behaviour, which have a tendency to recur; particularly patterns of behaviour that reflect deep psychological problems or extreme sociopathic preferences.
But I think it is difficult to understand how a past conviction could be used as evidence that the accused committed this particular offence today. Whilst a past conviction may suggest a psychological disposition to a certain type of behaviour, it does not prove that, on this occasion, this offence was committed by this individual.
Nor, as a matter of fact, does it prove a pattern of behaviour actually exists.
Unless, when the previous conviction was made, the existence of a pattern had been correctly established based on even earlier behaviour, the fact that the accused was convicted of an offence in the past must fall short of proving that the individual has a tendency to act in this way.
One instance of behaviour, which it may well have been, does not count as a pattern. Nor does it become a pattern by dint of being held up next to the current offence; it suggests the possibility of a pattern, but only if an assumption has already been made that the past offence was an instance of a behavioural disposition.
And in my view, this is precisely the prejudice that should not be allowed to creep in to our legal system. It would be too easy to make a mistake based on the assumption that if he has done it once, he is more likely to have done it twice.
Nor would it allow for the possibility that the previous conviction was incorrect and that a miscarriage of justice had occurred in the past.
It would be a disaster for our justice system if an individual, who was wrongly convicted in the past, yet was unable to prove his innocence afterwards, was nonetheless assumed to have committed this particular offence today, just because he has previous.