"Haven't you got any more questions for me?" asked the witness, when the lawyer appeared to have finished. "No," said the lawyer. The witness replied: "I also told the police that I'm registered blind."
The police's written account of this eyewitness's evidence had made no mention of this fact. It was, says Gerry Brown, a solicitor advocate and member of the Scottish Law Society's criminal law committee, a "very vivid example" of why defence lawyers should be sceptical about police witness statements when preparing their client's case.
In Scotland, there is only limited disclosure of police statements. To help preparation of the defence case, solicitors (or their agents) routinely visit and question witnesses to find out what they may be likely to say in court. South of the border, although there is no formal bar on their doing so, solicitors almost never approach witnesses - seeing the practice as "dodgy" or "bad form". Instead, in appropriate cases, they have been able to rely on cross-examining witnesses at committal to test their evidence and how it compares with the police account.
However, with old-style committals due to be scrapped later this year, solicitors are being urged by their professional body to follow the Scottish example. Roger Ede, secretary to the Law Society of England and Wales's criminal law committee, accepts the change will not be without problems. Although "precognition" of witnesses is a long-established practice in Scotland, in England and Wales it will be seen as a radical departure. The police are likely to be hostile to the idea of solicitors interfering with "their" witnesses, and victims groups may also be unhappy at the prospect.
Nevertheless, the introduction later this year of a wholly paper-based transfer for trial procedure means that solicitors will have to interview witnesses in some cases, Mr Ede says. Under the new system, solicitors will be supplied with copies of witness statements taken by police and, unless the defence applies for a dismissal, the case will be automatically transferred for trial. In exceptional cases, lawyers may be allowed to make oral submissions, but there will be no chance to question witnesses.
It is not only examples like the Scottish case that suggest how unreliable police witness statements can be. In one of the few studies into this area, Maxwell McLean, an inspector with West Yorkshire police, compared tape recordings of 16 police witness interviews with the subsequent written statements. He found the number of items omitted from the written account of the interview ranged from four to 38, with the average being 14. On four occasions, the officer wrote down a "fact" that contradicted what the witness had actually said. All the statements had been signed as a true record.
And no prizes for guessing which side's case the missing information would strengthen if it were included, defence solicitors say. Although they concede that the defence will have to question witnesses to avoid this kind of distortion, many have strong reservations about the practicalities.
Ian Ryan, solicitor to Colin Stagg who was cleared of the murder of Rachel Nickell, is appalled at the ending of old-style committals. Information gained during Mr Stagg's committal was crucial in getting the case thrown out by the judge when it came to trial, Mr Ryan says.
"At committal, only one of the five witnesses came up to proof. The whole thing would have been much more difficult if we hadn't been able to knock down so many of the elements of the case the police constructed round [Stagg] at that early stage."
In the Stagg case, interviewing a witness would have been no substitute for cross-examination at committal, says Mr Ryan. "I can't see any practical way of it working. In that case, the main witnesses were an expert and an undercover police officer. It would have been fraught with difficulties."
Even in less complex, less controversial cases, Mr Ryan has reservations about how the new system will work. Defence solicitors will be vulnerable to hostility from witnesses and to allegations of corruption from the police, he says.
The Law Society hopes to introduce safeguards to prevent these kinds of accusations. It recommends the police should usually be invited to sit in on the witness interview as an observer. But Steve Wedd, secretary of the Criminal Law Solicitors' Association, fears this may defeat the whole object of the interview. "Imagine the pressure on the poor sod who's being interviewed to stick to his original line if the policeman's sitting in the corner like a spider in a web."
Scottish solicitors say there is no need for this kind of precaution. Gerry Brown describes it as a "ludicrous" proposal. John Carroll, a former police officer and prosecutor, is equally opposed. "It sounds to me as if you might have a former chief inspector as president of your Law Society," Mr Brown says. "It will be intimidating for the witness, and for the solicitor as well. It is bound to restrict what the witness has to say."
The police also foresee problems. A spokesman for the Association of Chief Police Officers says there are insufficient resources to send officers to every interview. "We may have to confine ourselves to being present only where it is absolutely essential - probably at the request of the witnesses themselves," he says. Some witnesses are particularly likely to need moral support, for example, in a rape case.
However, Mr Brown says the defence can be sensitive to difficult cases without police intervention. "In a rape, we wouldn't send along some big bear of a man. We try to be sensitive to the situation. For cases of sexual abuse, we have a woman who is a former police officer with experience of working with child abuse cases."
Solicitors in England and Wales should be trusted to conduct interviews unchaperoned, as they are in Scotland, Mr Brown says. There may be times when solicitors will want an escort, however. Scottish precognition agents are sometimes subjected to harassment or even violence by the witnesses they have gone to interview - particularly where the witness is a friend or relation of the alleged victim.
Solicitors might be less vulnerable if interviews are conducted at their offices, but this is unlikely to be a regular option. Prosecution witnesses will not be keen to go to defence lawyers; the police station will not be a popular choice of venue with the defence, and, according to Mr Wedd, would increase the chances of the witness being pressured by the police. Nor are witnesses likely to want solicitors, with a police officer in tow, going to their workplace or home. "I can see they would love it - while his friends are in the pub, Johnny has to stay in to talk to a man in a suit, with a police car parked outside the house for all the neighbours to see," says Mr Wedd.Reuse content