Amnesty International’s mandate has centred on the release of ‘prisoners of conscience’, a fair and public trial for all political prisoners, and the abolition of torture and the death penalty. The term ‘prisoner of conscience’ (POC) was created by AI and includes anyone imprisoned because of their race, religion, color, language, sexual orientation, and so on. But it has an important exclusion. You are not a POC if you have used or advocated violence.
It is important to note here that AI is a membership organization and this mandate has been decided (and can be changed) by its 2 million something members.
Because her trial was conducted in closed sessions, the exact offending words used by Da Torpedo cannot be known for certain, but reliable reports indicate that she did advocate violence. She is therefore not a POC. And AI did protest publicly about the conditions of her trial.
And yes, Nelson Mandela is of course remembered. Because he publicly advocated the use of violence in his trial in 1964, AI decided then that he was not a POC.