A deaf defendant was facing rape charges and, after the Crown Prosecution Service had scoured the country, Mr Butterfield was the only available interpreter.
Incurring the judge's rage, he refused to work alone and breach deaf organisations' guidelines that at least two interpreters must be present to check and ensure accurate translation. A furious Judge Laughland claimed that the British Deaf Association and Royal National Institute For The Deaf were "interfering with the course of justice". Three months later the trial went ahead with two interpreters and the defendant was acquitted. "It could have been a gross miscarriage of justice," says Mr Butterfield.
As could a further case with a deaf defendant at Reading Crown Court last year. The judge was forced to send the jury home after a sign language interpreter braved court staff to say that the statement made by the deaf man in police interviews did not match what was being said in court.
This growing catalogue of cases illustrates that interpreting problems are leading to wasted time in court, mistrials and for deaf defendants a real fear that they will be unfairly convicted. "The issues here are civil liberty and the huge risk of miscarriages of justice for deaf people in the legal process," says Winifred Tumim, the wife of the former prisons inspector Judge Stephen Tumim. The couple also have a more personal interest in the issue as their daughter is deaf.
Mrs Tumim is now the chairperson of the UK Council of Deafness's working party on access to justice. The party was set up last year in the wake of a collapsed murder trial. At enormous cost, a retrial was ordered in the l0th week due to a sign language interpreting blunder.
The party's campaigning will be supported by research from the Access to Justice For Deaf People project at Durham University. The project has been monitoring the experiences of deaf people and sign language interpreters in courts for the past two-and-a-half years. The project director, Dr Mary Brennan, says these high-profile cases represent the tip of "a severe problem".
She explains: "In magistrates' courts and police stations some deaf people don't even get interpreters. Or if they do they can be so appallingly bad that they make matters so much worse for the deaf person." And, as the Reading case shows, throughout the legal process one interpreting mistake up to and including a court appearance could warp crucial evidence to catastrophic effect.
But the risk of thwarted justice for deaf defendants is also compounded by the dread that they are more likely to get a term behind bars as punishment. "If you are deaf you are far more likely to go to prison because there are also no interpreters to help supervise non-custodial sentences," says Mrs Tumim.
"It is extremely frightening," agrees Mike Reynolds, a probation officer. With 28 years' experience in the service he is also one of only three officers able to communicate with deaf people using advanced sign language. He details what he believes were unfair sentences passed while he was working as a senior probation officer at Winson Green prison, Birmingham. "I would say 75 per cent of those deaf convicts I saw would not have been there if they had had the benefits of a proper social inquiry done with interpreters before sentencing," he says. "When deaf people go to prison it is like a double sentence because they are effectively in solitary confinement. But ultimately, the probation service is just not equipped to make a range of sentencing options for deaf people."
Mr Reynolds, like others, cannot conceal his alarm at what he sees as gross injustice for deaf people in the legal process. "Nowhere in the country do deaf people have the same legal rights as hearing people. The courts' attitude to black people's rights is better than it was, women to a lesser degree, but with deaf people there is just a complete block."
At the root of this problem is a severe lack of interpreters for the UK's 62,000 deaf people whose first language is "signing". At present there are only 142 fully qualified British Sign Language interpreters. To exacerbate the situation there are no regulations in force on the hiring of interpreters and their standard of proficiency for legal work.
Stewart Simpson is chief executive of the Council for the Advancement of Communication with Deaf People, the body which trains and examines sign language interpreters. "This shortage of interpreters means people have to use trainee or sub-standard interpreters who are not up to the job and wrong messages are passed," he says. There are three grades of sign language proficiency and then a final qualification in interpreting. "But many interpreters don't want to work in the legal process anyway because it is complicated, the hours are uncertain in courts and many court staff are totally ignorant of deaf issues and very unhelpful."
As part of the package of measures to improve sign language interpreting in courts, Dr Brennan of the Access to Justice for Deaf People project recommends regulating interpreters. "Some are undertaking work which they should not be doing and it is causing more harm than good. In court you wouldn't use a barrister who wasn't properly qualified. Why do it with interpreters?"
Other solutions include videotaping all dialogue in the legal process from charging a suspect right through to the court case. Yet only Scottish courts allow their proceedings to be filmed.
Overall, more interpreters are needed. In 1992 a commission of inquiry into human aids to communication recommended emergency funding. Bob Peckford, director of advocacy services at the British Deaf Association, is adamant that funding is needed to avert a crisis. "The Government has a responsibility to provide these services in court. If not, we are just setting ourselves up for miscarriages of justice."
Mike Reynolds, there to see the process from court to jail, feels that injustice is worsened by ignorance. "Nobody knows how many deaf people are in prison. And nobody knows how many unjust convictions there are as the only evidence of bad interpreting is the trials that were stopped. But the real tragedy here is the question: how many other cases weren't stopped and as a result how many deaf people are in jail still unable to communicate their innocence?"