Born in Brussels to Belgian parents, Pevtschin grew up in a liberal Jewish household and was confirmed at the Great Synagogue in Brussels. She would later say that she was a confirmed atheist. She studied law, graduating from Brussels in 1937. When war broke out it became impossible for her as a Jew to practice law and she actively sought to resist the Nazi’s, joining the underground resistance group Service Zéro.
Within the group, Pevtschin was responsible for transmitting messages to London, providing false identity papers and establishing contacts with other Resistance networks in order to provide them with information for sabotage operations against the Germans.
Sold out by a traitor, she fell in Nazi hands and survived torture and imprisonment - no one ever realizing that she was a Jew. She endured a death march and further incarceration and forced-labour but survived the war, returning to her home country on foot. Within a few years, she had passed bar and she became a magistrate in 1948. In 1954 she was appointed the first Belgian member of the European Commission on Human Rights.
A defender of her Jewish heritage and an advocate of the universal right of law and of human rights, she passed away in 2001.