Note 15
From Reinhard Heydrich, by Joachim C. Fest— See further Notes

15 Hagen, The Secret Front, cites the outstanding example of Heinrich Muller, the Chief of Department Number IV in the RSHA (Gestapo) and a person noted for his air of secrecy, who until 1933 had even been an outspoken opponent of National Socialism. Frau Heydrich's remark about her husband's lack of political interest in the 1920s is recorded by Charles Wighton, Heydric. It was also Frau Heydrich who, having joined the NSDAP before her husband, awakened Heydrich's interest in politics.