Arthur Chaskalson: Key figure in South Africa after apartheid

Arthur Chaskalson was widely recognised as one of the key architects of South Africa's post-apartheid constitution, and also as its most renowned jurist. He burst into prominence as a junior barrister on the Rivonia Treason Trial defence team in 1963, building a lifelong friendship with Nelson Mandela and the other trialists, who were all sentenced to life imprisonment rather than death by hanging.

By then, he had already made his mark as a bright young thing in the legal world. He graduated Cum Laude with degrees in commerce and law from Wits University in 1954 before being admitted to the Bar two years later. He took Silk in 1971, but having grown up in a Jewish family with a strong sense of social justice, the career path of the commercial lawyer never excited him. Rather, his energies went into opposing the government's apartheid laws and defending its opponents at a time when public opposition was dormant.

Chaskalson was never one of those hectoring, caustic, showman barristers epitomised in television dramas. Instead, his reputation was as a deep thinker, and, when required, an incisive cross-examiner. Those who knew him well talked about both his brilliant intellect and his apparent lack of ego.

In 1978 he took a decision that seemed to go against the careerist grain by becoming the first director of the non-profit Legal Resources Centre, which was dedicated to public and human rights law, while also serving as a board member of the legal faculty of his alma mater. The National Party government regarded him as an enemy, but his position and international reputation (which included membership of the New York Bar Association) meant they could not hit him directly, although they would never appoint him to the bench.

However, he was already preparing for his future role, helping the Namibian Constituent Assembly draft its new constitution. And when the African National Congress was unbanned in 1990, Chaskalson became a member of its constitutional committee, and went on to serve on the technical committee at the Codesa negotiations forum, playing a central role in drafting the country's new constitution. An interesting side note is that he had joined the banned South African Communist Party in the early 1960s, but was never active in the underground thereafter. Still when he first arrived at Codesa, it was as a Communist Party delegate.

It came as no surprise when his friend Mandela appointed him as the president of the country's new constitutional court, whose first task was the certification of the new constitution. While this was happening, he was robbed in his own home.

"He told us that the solution to a difficult constitutional problem came to him when he was down on his knees with a gun pointing to his head," fellow jurist Dr Albie Sachs recalled. "He laughed about it, but it showed that even in such a moment of peril, his brain never stopped working. He really had a magnificent legal mind – one of the finest of the 20th century – and he put the law and the constitution before anything else."

Several of his judgments, including his first, on capital punishment, have been widely cited internationally, but Chaskalson also developed a reputation for his collegiate approach on this new, non-racial constitutional court. "I loved working with him," said Sachs. "He got on with everyone because he was very fair, very wise, a wonderful listener and he was modest in his style. When offered a BMW, he turned it down and took a Toyota instead."

Another Constitutional Court judge, Edwin Cameron, spoke of Chaskalson's compassion. "I was living secretly with HIV and I'd been nominated to become a judge. Arthur showed that personally supportive, loving side of him. He insisted I allow my nomination to go forward, and later, also with his personal encouragement, I made a public statement."

In 2001 Chaskalson's title was changed to that of Chief Justice of South Africa, a role he held until 2005. In his last address from the bench he stressed the need for separation of powers between the judiciary and other branches of government. "Experience shows that where there is absolute power, corruption and abuse of power are more likely ... It is important for our democracy that the delicate balance be kept intact."

He watched from retirement as his government fiddled with that balance – attempting to introduce restrictions on press freedom and to appoint compliant judges. But by then, he had moved on, and was well-established as an international jurist, having been appointed to the UN Permanent Court of Arbitration and later as judge at the International Criminal Tribunal for the Former Yugoslavia. Chaskalson died of leukaemia.

Arthur Chaskalson, jurist, born Johannesburg, South Africa 24 November 1931; married Lorraine (two sons); died Johannesburg 1 December 2012.