Truck driver Kevin Callan had left school at age 16 without any academic qualifications. But a relentless determination to prove he was innocent of a murder for which he had been convicted drove him to become expert on studies of the human brain.
After four years of study inside a prison cell, Mr. Callan forced Britain's legal authorities to admit that supposedly expert prosecution testimony at his trial had been wrong and that he had not been responsible for the death of a four-year-old child.
On April 6, 1995, Callan walked from Britain's Appeals Court a free man. He joined the ranks of a growing number of people wrongfully convicted by Britain's legal system who have had to be released from prison following campaigns to establish their innocence.
The last few years have seen a series of such instances, forcing the government to set up an independent body to investigate miscarriages of justice.
Most of the instances have centered on people accused of terrorist acts on behalf of the Irish Republican Army (IRA). The cases of the "Birmingham Six," the "Maguire Seven," and the "Guildford Four," in which the accused were jailed for terrorist bombings, are perhaps the most notorious. They attracted huge publicity in Britain and around the world. Police evidence provided at their trials was later shown to be flawed.
Chris Mullin, a Labour party member of parliament who took a close and active interest in the Irish cases, says two key factors created the circumstances for injustices to occur.
"There was a highly charged political atmosphere," Mr. Mullin says, "because there was widespread revulsion against terrorist acts, particularly those carried out on the British mainland, and this inevitably had an effect on how the judicial process operated.
"Also, at the time it was not widely appreciated by the public at large that police evidence was crucial in influencing the outcome of trials," Mullin adds. "When the basis of that evidence was shown to be false or highly dubious, the cases had to collapse."
The Irish victims were fortunate in having champions such as Mullin acting on their behalf, whereas Callan had to rely on his own tenacity and courage in fighting for his freedom virtually single-handedly, and without the benefit of publicity in the early stages.
Michael Mansfield, Callan's legal counsel, says that like the better-known Irish cases, Callan's struggle exposed the "extraordinary reluctance" of the British authorities to concede that "terrible mistakes can be and are being made. There are obvious flaws in our justice system, and the Irish cases and that of Mr. Callan have served to expose them," he says.
Callan's long ordeal began on April 15, 1991 when he was looking after Amanda, the infant daughter of his partner, Lesley Allman, in the home they shared in Manchester, England.
Amanda was severely handicapped and often fell over in the house. She had done so twice that day, the second time fatally. Miss Allman returned home to find Callan trying unsuccessfully to resuscitate the child.
After a police investigation, Callan was charged with murder.
In the trial that followed, a key prosecution medical witness testified that the girl's death had been caused by her being violently shaken. The witness said he could see no sign of external bruises consistent with any fall.
Despite testimony by Allman that he loved Amanda and had never harmed her, Callan was sentenced to life in prison.
There, certain of his innocence, he asked the prison librarian to supply him with books about the human brain. "I thought that if I could find out how [the brain] works, I could learn how Mandy had died," he says.
Study was a new experience for Callan, but within eight weeks he had read a dozen books.
Soon he felt qualified to move beyond reading. He began writing to the books' authors and to some of the experts quoted.
He sent a letter, for example, to Philip Wrightson, an expert in neuropathology in New Zealand. He opened a correspondence with Helen Whitwell, a neurology expert at the British Home Office in London. He requested post-mortem photographs of Amanda and asked the experts' opinion on them.
When the replies began flowing in, they were startling: The specialists agreed that Amanda must have died from a fall.
Armed with evidence contradicting the prosecution testimony at his trial, he asked the Home Office to review his case.
At first his appeal was rejected. But Callan persisted. With his lawyer's help, he managed to persuade the Crown Prosecution Service to commission its own study from a brain expert. For the prosecution, the result was devastating.
The testimony of its "expert" witness "left much to be desired," says Michael Green, a professor in forensic pathology at Sheffield University. The witness's view that death had been caused by shaking was "difficult to justify." In the end, the prosecution had no option but to ask the Appeals Court to rehear the case.
Ordering Callan's immediate release, the three presiding judges said the fresh evidence "renders this conviction completely unsafe and unsatisfactory." It was, they declared, "a matter of regret that the applicant should have been convicted in the first place."
Mansfield says: "There is a cautionary tale here both for the lawyers and the courts."
He is by no means alone in believing that the Callan case exposed grave weaknesses in Britain's legal system.
Mullin is critical of what he calls the "sluggish reluctance" of the Home Office to refer cases to the Appeals Court, and of the court's diffidence in hearing new evidence.
He notes that although up to 800 applications are submitted for review each year, only a tiny fraction ever get back into court. He also recalls that in July 1993 a government-appointed commission on criminal justice criticized the Home Office for using its power to refer cases too "restrictively."
At the root of the problem Callan and other victims of miscarriages of justice have faced, Mullin says, is "a tendency by our legal establishment to put up obstacles to strong, well-based attempts to put things right."
Largely thanks to blunders the courts made in the Birmingham Six and Guildford Four campaigns, and Home Office lethargy in responding to appeals, the government moved last February to set up an independent body to investigate alleged miscarriages of justice.
Instead of the Home Office handling requests for reviews, a Criminal Cases Review Commission will have power to recommend that cases be returned to the courts.
But the new system, which will begin to operate late this year, does not satisfy critics like Mullin and Mansfield.
Mullin criticizes the government for failing to give the new body its own team of investigators. Instead, investigations will be carried out by police. This, Mullin says, is to "build into the new system one of the central weaknesses of the old."
Mansfield describes the creation of the new investigating commission as "a step in the right direction," but adds that it does not alter the fact that if Callan had not been so incredibly dogged, he would probably still be in jail.
Callan, meanwhile, is seeking financial compensation from the government for wrongful imprisonment.
*Third in an occasional series. Parts 1 and 2 ran March 27 and June 26.