On 8 November 2011, Weber was officially appointed by president Dilma Rousseff for a position left by the retirement of justice Ellen Gracie Northfleet in the Supreme Federal Court.

[7] During the session, two senators voiced against her nomination: Demóstenes Torres (DEM-GO) - who would later be removed from office - and Pedro Taques (PDT-MS).

They stated that Rosa Weber did not demonstrate that she had the constitutional requirement of "remarkable legal knowledge" during the hearing, as she didn't answer many questions made by the senators.

[8] Sworn in at the morning of 19 December 2011, she is the third woman to be part of the Supreme Court, being the first Ellen Gracie, who Weber replaced, and Cármen Lúcia, who's still in office.

[13][14] Daughter of physician José Júlio Martins Weber and rancher Zilah Bastos Pires, she is married to Telmo Candiota da Rosa Filho, retired prosecutor of Rio Grande do Sul, with whom she had two children.