She previously was senior counsel for the Southern Center for Human Rights.

From 2003 to 2022, she was with the Southern Center for Human Rights in Atlanta and from 2015 to 2020 served as managing attorney of the Impact Litigation Unit.

President Biden nominated Geraghty to the seat vacated by Judge Amy Totenberg, who assumed senior status on April 3, 2021.

[4] On January 3, 2022, her nomination was returned to the President under Rule XXXI, Paragraph 6 of the United States Senate;[5] she was later renominated the same day.

[10] On August 21, 2023, she blocked a Georgia law banning hormone therapy for transgender minors,[11][12] but the United States Court of Appeals for the Eleventh Circuit overturned her ruling, which prompted her to allow the ban to be enforced on September 5, 2023.