Jim MacKeith was a forensic psychiatrist who took an active interest in cases of miscarriage of justice, particularly those concerning false confessions. He helped to secure the release of the Guildford Four, the Birmingham Six and Judith Ward, all wrongly jailed for IRA bombings, and a man who spent a quarter of a century in prison for a murder he did not commit.

MacKeith became involved with the pub bombings cases when he was asked by the Prison Service to review the confession of one of those jailed. On reading his findings, the solicitors representing the others asked him to look into all the confessions. His subsequent report threw doubt on the conviction of all ten and led to the cases being reviewed. The convictions were later quashed on other evidence.

MacKeith gave expert evidence in the appeal of Ward who was then released 18 years after being jailed for a series of bombings, including a coach on the M62. He also testified in the appeals of Andrew Evans and George Long who spent 25 and 16 years in jail respectively for the separate murders of two children in the Seventies. In each case MacKeith found that confessions had been made while the suspects were suffering from mental instability.

MacKeith’s interest in false confessions began in 1978 when he acted as an expert witness in a case of a man he believed had wrongly admitted guilt during interrogation. This led to further research and the presentation of a paper, written with his psychology colleague Gisli Gudjonsson, on false confessions at an international conference in Stockholm in September 1981. There was general scepticism among lawyers and psychologists about the phenomenon, but MacKeith and Gudjonsson continued their research and discovered that false confessions were not confined to people with mental disorders. They developed a conceptual framework for evaluating cases of disputed confession, which has influenced scientific thinking and clinical practice.

In 2004 he co-wrote a report condemning the treatment of foreign terror suspects held in Belmarsh prison. He also lent his weight to campaigns on behalf of British detainees in Guantanamo Bay that eventually resulted in their freedom.

James Alexander Culpin MacKeith was born in 1938 in Leamington Spa, Warwickshire, the eldest of six children. His father, Stephen, was a medical doctor and worked in psychiatry. MacKeith spent the war with his mother in native Australia, and in his early years he saw very little of his father, who served with the Army Medical Corps. After the war the family moved to the grounds of a psychiatric hospital in Norwich, where MacKeith’s father was working. It was during this time that he developed his interest in sailing, with frequent trips on the Norfolk Broads.

MacKeith was educated at Epsom College School and after failing to gain entry to a medical school in Britain, obtained his medical qualification from Trinity College Dublin in 1965. He later gained a diploma in psychological medicine in 1972 and also became a member of the Royal College of Psychiatrists. He also completed an MA that included English literature, psychology and social and political institutions. It was while studying in Dublin that MacKeith became interested in Irish affairs, leading him later to take a personal and professional interest in those wrongly convicted of IRA murders.

Between 1972 and 1974 MacKeith worked as a medical officer at Brixton Prison. In 1974 he became a consultant forensic psychiatrist at Broadmoor Hospital where he worked until 1977 when he took up a similar position at the Bethlem Royal and Maudsley Hospital.

He also became regional adviser for forensic psychiatry at the South East Thames Regional Health Authority. This involved major advisory roles in the planning and setting up of five medium secure units in the South of England. In spite of enormous local opposition, MacKeith was able to use his exceptional diplomatic and inter-personal skills to see all the units open and prosper. This was in his view one of his proudest professional achievements.

MacKeith retired from the South London and Maudsley trust in 1999. He is still fondly remembered by his colleagues of all disciplines — medicine, nursing, occupational therapy, social work and psychology — for his humanity and clinical skills. He took great interest in the welfare of his colleagues and was always accessible when needed for advice or support.

MacKeith was an exceptional mentor, teacher and tutor. He took an active part in the training of junior staff and taught them clinical skills and good ethical practice.

He had a long-lasting impact on the development and practice of forensic psychiatry, psychology and law. He showed great humanity to patients, friends and colleagues and his inspiring and congenial presence will be greatly missed.

MacKeith was heavily involved in the Murray Cox Foundation, named after a Broadmoor psychiatrist who believed in the benefit to patients of reading and watching Shakespeare.

In 1997 he became a commissioner of the Criminal Cases Review Commission, retiring last year. From 1991 to 2006 he was an expert adviser to delegations visiting countries on behalf of the Council of Europe Committee for the Prevention of Torture and Inhuman or Degrading Treatment or Punishment.

In 1992 he was elected Fellow of the Royal College of Psychiatrists. He was appointed OBE in this year’s Queen’s Birthday Honours for services to the criminal justice system.

He is survived by his wife, Keesje van Erkelens, a psychoanalyst whom he married in 1973, their daughter and two sons, both of whom are following medical careers.

Dr Jim MacKeith, OBE, forensic psychiatrist, was born on October 29, 1938. He died of cancer on August 5, 2007, aged 68