The 1888 Constitution of Kingdom of Serbia contains one provision about non-extradition for political crimes. In this paper, the authors will analyze the Belgian influence on Serbia regarding the acceptance of the rules on extradition. Belgium, born in 1830 out of a liberal bourgeois revolution, was the first country to vote a very influential Act on extradition in 1833, containing the principle of non-extradition in case of political crimes. In 1856, the Jacquin case led to the so-called ‘Belgian clause’, introducing an exception on this non-extradition principle for political criminals who tried to assassinate a ruler or member of his family. The authors will discuss if political circumstances in Serbia have had influence on the normative regulation of this issue.