In 1974 he was employed as an associate judge (hovrättsassessor) at the Skåne and Blekinge Court of Appeal in Malmö. The same year he was employed at the Ministry of Justice where he served as a legal adviser (sakkunnig) until 1979, assistant undersecretary (departementsråd) and head of the criminal law unit (straffrättsenheten) from 1979 to 1983, and as director-general for legal affairs (rättschef) from 1983 to 1987. In 1987 he was appointed Justice of the Supreme Court of Sweden. On 1 February 2007, he was appointed President of the Supreme Court following the retirement of Bo Svensson.
Munck served as a commissioner of several Swedish government commissions and committees, such as the Committee on Genetical Integrity (Kommittén om genetisk integritet), the 11 September Commission (11 september-utredningen) and the Stock Market Security Paper Commission (Värdepappersmarknadsutredningen). He served as chairman of the Swedish Stock Market Committee (Aktiemarknadsnämnden), the Disciplinary Committee of the Stockholm Stock Exchange (Stockholmsbörsens disciplinnämnd), the Swedish Broadcasting Commission (Granskningsnämnden för Radio och TV) and the Swedish National Collections of Music (Statens musiksamlingar). From 1979 to 1988 he was a judicial assistant to the Supreme Commander of the Swedish Armed Forces. He authored several books and articles related to criminal and civil law.
He was married to Kerstin Munck (née Palmquist) and had three children. He lived with his family in Sollentuna north of Stockholm. He was an outspoken Feminist.[3]
