Mouvement Réformateur
Soustelle was elected to France's National Assembly (France's lower House) three times, first representing Mayenne in 1945–46, then the Rhône (1951–58) as a Gaullist, and from 1973 to 1978 as a member of the centrist Mouvement Réformateur. In 1974, he supported the bill legalizing abortion presented by Simone Veil.