When World War II ended, Weidinger was held at the Dachau internment camp administered by the US Army. In August 1947, he was transferred to French custody, where he was charged with war crimes and stood trial in 1951. Weidinger was acquitted by a military court in Bordeaux in June 1951. At the trial of the perpetrators of the Oradour-sur-Glane massacre in Bordeaux in January 1953, Weidinger was a witness for the defense.