Since 1994 he heads the Chair of Criminal Law of the Jagiellonian University.

[1] In 1989 he took part in the Round Table Negotiations as Solidarity’s legal expert.

[3] Between 1989 and 1993, he served as a judge of the Polish Constitutional Tribunal and between 1990 and 1993 he was chairman of the State Electoral Committee.

[3] In 2002, he was appointed deputy director at the European Ombudsman Institute.

[3] He is also the author of 3 monographs and above 150 other publications in the area of criminal and constitutional law and philosophy of law, and a member of the Committee on Ethics of the Polish Academy of Sciences, as well as the Department of History and Philosophy of the Polish Academy of Learning, and Curator of the Association of Law Students' Library of the Jagiellonian University.