[4] In 2011, Cariou joined Arnaud Montebourg's campaign for the Socialist Party's primaries ahead of the 2012 presidential elections, advising him on tax policy.

[6] Shortly afterwards, Cariou followed Fleur Pellerin to the Ministry of Culture and Communication, where she was in charge of copyright issues within the European Union.

[7] In May 2014, Cariou became deputy director responsible for budget and financing at the National Centre for Cinema and the Moving Image (CNC).

[12] In July 2019, Cariou announced her candidacy to succeed Carole Bureau-Bonnard as vice-president of the National Assembly;[13] in an internal vote, she lost against Laëtitia Saint-Paul.

[17] In July 2019, Cariou voted in favor of the French ratification of the European Union’s Comprehensive Economic and Trade Agreement (CETA) with Canada.