Hungary's government expressed its "deep outrage" Thursday over recent criticism of its judiciary by EU justice Commissioner Viviane Reding.
In a March 9 article in the German daily Frankfurter Allgemeine Zeitung, Reding said Ireland's reluctance to extradite an Irish national to Hungary over a fatal car crash was "understandable".
"I was not surprised - after all, this was precisely during the time when many decisions were taken in Hungary which raised serious questions about the independence of the Hungarian justice system," Reding said.
In 2000, Ciaran Francis Tobin, an Irish businessman working in Budapest at the time, killed two Hungarian children with his car in a village close to Budapest. He was convicted in Hungary in absentia.
After joining the European Union in 2004, Hungary issued a European Arrest Warrant for Tobin to force him to serve a prison sentence but the Irish Supreme Court refused to extradite Tobin on two separate occasions.
"The Hungarian Ministry of Justice expresses its deep outrage at a remark made by Viviane Reding connecting criticism of the Hungarian judiciary with the Tobin case," a statement from the ministry said.
In an open letter at the weekend, Hungary's Justice Minister Tibor Navracsics asked Reding to "kindly refrain from making public statements that lack sufficient grounds as well as harbouring general malice".
Brussels has long expressed concerns about the independence of Hungary's judiciary under Prime Minister Viktor Orban, as well as about other key democratic institutions. On March 11 the government changed the constitution and curbed the powers of the constitutional court.