The European arrest warrant established in 2002 is an important tool in prosecuting perpetrators of crimes committed within the European Union. It can, however, be considered as some interference in state sovereignty. Such a situation took place in 2013 when Croatia joined the EU. Just before the date of accession the parliament changed the law, significantly limiting the possibility of extraditing the citizens of that country to the other EU countries. The unofficial, but actual reason for this decision was the desire to protect the former high-rank representative of the Yugoslavian secret services, Josip Perkovic, accused of participating in the assassination of a Croatian dissident in Germany in 1983. This risky step by the Croatian authorities has led to a serious crisis in relations with the German government and the European Commission, including the threat of EU funds being withheld. He even got a separate treatment in the literature on the subject (lex Perković, Croat slučaj Perković). The main purpose of the article is to present and discuss political events that accompany this case, as well as to analyze legal steps taken by all interested parties.