Lothar Fendler (born 13 August 1913 in Breslau; date of death unknown, after 1951) was an SS-Sturmbannführer, in Sonderkommando 4b of Einsatzgruppe C and was involved in the murder of the Jews in occupied Ukraine. At the Einsatzgruppen Trial in 1948 Fendler was sentenced to ten years in prison but was released in 1951.
Between 1932 and 1934 Fendler studied dentistry. On 15 April 1933 he joined the SS, service number 272,603. From 1934 to 1936 he served in the Wehrmacht. After leaving the Wehrmacht Fendler joined the Sicherheitsdienst (SD) in 1936. On 1 May 1937 he joined the NSDAP (number 5,216,392). In May 1941, Fendler was transferred to Sonderkommando 4b of Einsatzgruppe C to prepare for the Einsatzgruppe actions during Operation Barbarossa, where he was responsible for divisional intelligence. His role according to his testimony at Nuremberg was to write reports on the morale of the local population. On 2 October 1941 he was replaced and returned to Berlin. He was posted back to the Sonderkommando in March 1942 and returned again to Germany in July of the same year. He spent the rest of the war working for SD foreign intelligence. He was subsequently arrested by the Americans and put on trial at Nuremberg.
From 1947 to 1948, Fendler was one of 24 defendants in the Einsatzgruppen Trial; his defence lawyer was Hans Fritz with the assistance of Dr. Gabriele Lehmann. The presiding judge was Michael A. Musmanno. On 9 April 1948 Fendler was found guilty on the three charges with which he was charged: (1) Crimes against humanity, (2) war crimes, and (3) participation in a criminal organization. The case against him was based on the question of whether Fendler reported as deputy leader to Günther Herrmann; this was not conclusively answered. Fendler was certainly Herrmann's second-highest-ranking officer in Sonderkommando 4a and there were only seven officers in the unit. On 10 April 1948 Fendler was sentenced to ten years in prison.
He served his sentence in Landsberg prison. As part of the intensified discussion of West German rearmament after the outbreak of the Korean War in the summer of 1950, on 31 January 1951 High Commissioner for Germany John McCloy assessed the 15 death sentences handed down at Nuremberg on the recommendation of the "Advisory Board on Clemency for War Criminals". Four inmates had their sentences commuted to life imprisonment and six given prison sentences of between ten and twenty-five years, but confirmed that five of the death sentences should be still enforced. The judgment against Fendler was reduced to eight years. In December 1951 he was released from prison.