"He is not aware of anything that he must apologise for," Mr Botha's lawyer, Ernst Penzhorn, said.
Mr Botha, 82, was on trial for snubbing the Truth and Reconciliation Commission, which is investigating apartheid crimes. If found guilty, Mr Botha faces an unspecified fine or two years in jail.
Prosecutor Bruce Morrison said Mr Botha, nicknamed the "Big Crocodile" for his stubborn political style, had deliberately defied the commission. "His refusal to attend is the result of a wilful and deliberate defiance," Mr Morrison told Judge Victor Lugaju.
Desmond Tutu, chairman of the Truth Commission, had appealed for Mr Botha to apologise publicly for the brutalities of his government. Mr Tutu had said earlier this month that such an act of contrition would help heal racial problems still plaguing the country.
Mr Penzhorn said Mr Botha had been "astonished" by Mr Tutu's statement.
Mr Botha ignored three subpoenas to appear before thecommission, which wanted to question him about his role as head of the State Security Council, a body that coordinated a security crackdown on anti-apartheid groups.
Meanwhile, South Africa said yesterday an apartheid-era chemical and biological weapons programme had been wound up and its material for offensive purposes destroyed.
A statement issued bygovernment spokesman Joel Netshitenzhe said the termination of the programme was done in cooperation with countries which possessed the necessary expertise. It did not indicate when the programme was closed down.Reuse content