Haffejee's brother Yusuf asked the commission at its Durban hearings to help his family in their "quest for justice".
He said the family rejected the outcome of a 1978 inquest which found that nobody was responsible for his brother's death.
The 26-year-old dentist was found hanging from a grille door at Durban's Brighton Beach police station shortly after being arrested in possession of "subversive documents" advocating a revolution to set up a socialist people's republic.
At the inquest, legal counsel for the police had presented Haffejee as a dangerous terrorist who had committed suicide because he knew he faced the possibility of long term imprisonment, his brother told the commission on Wednesday.
Although the inquest heard that Haffejee's body had injuries to the neck, shoulders, knees and ankles, police claimed he had sustained these after refusing to get into a car.
Yusuf Haffejee said the family would oppose any attempt by his brother's alleged killers to apply for amnesty.
"They should be hunted down, tried and punished. There can be no amnesty for murderers and torturers," he said.