Dr Basson, who is also known as "Dr Death", was the head of the government's biological weapons unit. He was cleared of 46 charges of murder, conspiracy and drug trafficking by the Pretoria High Court in 2002 after he claimed he had merely followed state orders and had worked to combat a potato blight and an epidemic of hepatitis A.
Yesterday, the constitutional court ruled that the state could retry Dr Basson on six charges of conspiring to commit offences beyond South Africa's borders. Dr Basson can now be charged with conspiracies to murder anti-apartheid activists in Namibia, Moz-ambique, Swaziland and the UK. The six charges were rejected by Judge Hartzenberg in 1999 on the basis that crimes committed abroad could not be tried under South African law, but the constitutional court ruled that South Africa had an obligation under international law to try those accused of war crimes.
Judge President Pius Langa, who handed down the judgment yesterday, said there was a real and substantial connection between South Africa and the alleged crimes. Dr Basson was accused of trying to create "smart" poisons that would only affect the black community and to have ordered political prisoners to be tied to trees and smeared with poisonous gels overnight. If they survived they were later killed by muscle relaxants.
He is also accused of having manufactured enough cholera and anthrax in his laboratories to start an epidemic and injected chocolates and sugar with sal-monella and botulism. He also allegedly laced whiskey with herbicide.
During his earlier trials, former agents with the state's Covert Cooperation Bureau, a secret assassination unit, claimed that Dr Basson and his team had supplied poisons.
One former Special Forces officer, Johan Theron, told how the government had decided to execute hundreds of prisoners to cope with the problem of overcrowding in jails and asked Dr Basson to supply the means.
A retired French Foreign Legionnaire also claimed he saw Dr Basson injecting five guerrilla rebels from the Zimbabwe African National Liberation Army with poison and throwing them alive from an aeroplane in 1979.
In dismissing the charges against him, Judge Hartzenberg ruled that Dr Basson had been the victim of a witchhunt by people far more "repugnant" than him. He also admitted he was "bored to death" with all the documentation and refused to travel to England to hear testimony from a former British secret agent.
The ruling African National Congress party said the decision to clear him of all charges was dangerous for race relations. Smuts Ngonyama, an ANC spokes-man, said the case was, "a clear case of the protection of an individual who has killed people".
After he was freed in 2002, Dr Basson said the money the state had spent prosecuting him could have been better spent providing anti-Aids drugs. He also denied that he had embezzled state funds and said he had been given a blank cheque by the government to carry out his work.
The South African government, which spent more than £2m on the prosecution, has always maintained that he was treated too leniently by Judge Hartzenberg. Now the Supreme Court has vindicated that opinion.
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