[1][4] Lietz, who had joined the ruling Socialist Unity Party (SED) in 1949, became a full-time party functionary in 1954, working as a staff member and later as a sector leader for Agricultural Production Cooperatives (LPGs) and MTS in the Agriculture Department of the SED Central Committee.

[1][4][5] Lietz further climbed the party ranks when he was elected as a candidate member of the Central Committee of the SED in January 1963 (VI.

[1][4][6] Longtime head and famed Stakhanovite activist Bruno Kiesler officially retired of his own will, but was actually dismissed due to his disagreements with the SED's economic policies.

[8] Lietz additionally became a member of the Volkskammer in June 1986,[1] nominally representing a rural constituency in western Bezirk Halle.

[1] During the Peaceful Revolution, on 7 November 1989, he resigned alongside rest of the government led by Willi Stoph and retired in 1990.