Thea Illsley is a senior lecturer in procedural law and has the following qualifications: BLC LLB (Pret), LLM (UNISA), LLM (McGill) as well as a Diploma in Dispute Resolution. She is also an attorney of the High Court. Having completed her LLB in 1990, Thea served articles for two years at Gildenhuys van der Merwe Inc and subsequently took up a position at UNISA as editorial assistant for the publication Rights and constitutionalism : the new South African legal order . In 1994 she was appointed as lecturer in the Department of Criminal and Procedural Law, teaching Law of Evidence on undergraduate level. As from 1 January 1996 she was appointed as senior lecturer. From August 1995 until April 1996 she studied towards an LLM at McGill University in Montreal, Canada. She took up a position as senior lecturer in the Department of Procedural Law at the University of Pretoria in December 1999. She is currently senior lecturer in the Law of Evidence and Advanced Law of Evidence.

Her main areas of interest are general aspects of the Law of Evidence, Aspects of Sexual Assault Law as well as Media law.