In 1994, Omar became Minister of Justice in South Africa in Nelson Mandela's ANC government, and was the first cabinet minister appointed Acting President in the absence of both the President and Deputy President from South Africa. He played a major role in transforming the South African justice system. One of his principal actions was the promulgation of the Truth and Reconciliation Commission in July 1995 to look into the crimes committed during apartheid and offer platforms for victims and/or their families to confront the perpetrators, who would in turn be offered amnesty for coming forward. The model served as an inspiration for other post-conflict societies in places such as Sierra Leonne and Rwanda.