After his arrival in Spain controlled by the fascist insurgents, he held various positions. Winzer oversaw Miranda de Ebro's Concentration Camp, built by fascist forces inspired by German concentration camps such as the one in his hometown, and in turn the Miranda de Ebro camp served as a testing ground for Nazi camps in Central Europe. Some authors point to Winzer as one of the designers of the structure of the camp, while others point to him as the designer of the entire Francoist concentration camps system. 