Seifert went unpunished for nearly 50 years, until in 1994 new documents were found in Italy about the crimes committed by the occupying power during World War II. In 1999, an Italian Prosecutor began proceedings against Seifert, of which he was immediately notified.
On 24 November 2000, the Military Tribunal of Verona condemned him in absentia to life imprisonment, on 18 counts of murder and torture. He was found guilty for the murder of 11 prisoners, and for the torture of many others. Seifert admitted to have been a guard at the Bolzano camp, but continued to maintain his innocence concerning the accusations of murder and torture. He therefore appealed against the guilty verdict to the Military Court of Appeal, which confirmed the judgment on 18 October 2001. He made a new appeal to the Italian Court of Cassation, which was also rejected on 8 February 2002.
In May 2002, he was arrested in Vancouver. He was released on bail in April 2003. In August 2003, the Federal Court of Canada ordered his extradition. This decision was confirmed in 2004 by another provincial court. Seifert then made an appeal to the Minister of Justice. In December 2005, the Canadian Minister of Justice rejected Seifert’s appeal against the extradition decision and ordered him to surrender to the Italian authorities. In August 2007, the Court of Appeal of British Columbia confirmed the extradition request and ordered that Seifert be detained. The Court also rejected Seifert’s appeal that was based on the argument that the judge at the original trial was biased because of his Jewish origins. On 17 January 2008, the Canadian Supreme Court refused to deliver a verdict on Seifert’s appeal, thereby paving the way for his extradition to Italy. He was extradited to Italy on 15 February 2008 and immediately imprisoned.
Due to his age and poor health, Seifert was soon able to take advantage of kinds of punishment alternative to imprisonment.
In addition, from April 2002, procedures for the revocation of Canadian citizenship were launched in conjunction with the court proceedings. In November 2007, a federal court authorised the forfeiture of the Canadian citizenship acquired by Seifert, due to the fact that his entry into the country was based on a distortion of reality and on the lack of disclosure of important material facts.
Micheal Seifert died in Italy on 6 November 2010, at the age of 86 years.