Brenier joined the UMP in 2007.[2]
In 2008, she was elected municipal councillor of Nice (although she began serving only in 2009),[3] where she was tasked with overseeing sports affairs.[4] In April 2014, she became a territorial deputy mayor of Nice under the leadership of Christian Estrosi.[5] The following year, she was elected as a departmental councillor.
From 2015 to 2017, Brenier served as president of the Young Republicans, succeeding Stéphane Tiki.[6]
In parliament, Brenier served on the Committee on Sustainable Development and Spatial Planning (2016–2017) and the Committee on Social Affairs (2017–2022).[7]
From 2018 to 2022, Brenier was a member of Soyons libres (SL), founded and led by Valérie Pécresse.[8] In 2021, she led a group of LR deputies pushing for more liberal rules on assisted suicide.[9] [10]
Brenier was a candidate in the 2022 legislative elections.[11] Her candidacy was endorsed by Nicolas Sarkozy.[12] She lost her seat to Christelle d'Intorni from the National Rally in the second round.[13]
Following her defeat in the 2022 legislative elections, she returned to her role as deputy mayor of Nice, overseeing Family and Early Childhood affairs.[14]
