Madsen was a paralegal in Esbjerg. He briefly worked for the By- og Herredsret in Sæby and Frederiksberg Birk in 1909–10 before his employment as an assistant in the Ministry ofFinancial Aggairs later in 1910. He worked as a copyist at the Landsoverret and Hof- og Stadsret-ten from 1015 and as a police accessor in Copenhagen from 1919. On 25 July 1919, he was licensed as a high court attorney. He was employed as a Police Attorney in 1028. He resigned in 1934 due to illness.