St. Amant began her journalism career at People Newspapers in Dallas, where she won two Philbin Awards for excellence in legal reporting.[5][4][2] At age 24, she conducted an investigative series on a faked home invasion, which led to her recruitment by CBS News.[4][5] She served as a founding editor of CultureMap Dallas before joining CBS News in 2014.[5][1][2]
At CBS, she developed and produced crime stories, contributing to over 20 episodes of 48 Hours. Her work included coverage of an assassination attempt on a judge in Austin, Texas, a serial killer in South Carolina, and a murder-for-hire plot involving two doctors in Houston.[3][2][1]
In 2016, she was part of the breaking news team for the special report “Bringing a Nation Together” on the 2016 Dallas police shooting. The report won a New York Press Club award and earned the team an Emmy nomination for Outstanding Coverage of a Breaking News Story in a News Magazine.[3][2]
In 2019, she contributed to a 60 Minutes segment titled “The Ranger and The Serial Killer.”[3][2][1]
St. Amant is the writer, producer, and host of the true crime podcast Final Days on Earth, which investigates mysterious deaths and cold cases through multi-episode series, including cases such as the 2014 death of Dammion Heard (Season 1),[6] the 2002 disappearance and death of Jennifer Harris (Season 2),[7] and the 2011 murder of Greg Williams (Season 3).[1][2][8]
In 2024, she was named the Radford Visiting Professor in the Department of Journalism, Public Relations & New Media at Baylor University, where she teaches a class on podcasting.[1][4][5]
Her memoir, Killer Story, was published in 2025 by BenBella Books and distributed by Simon & Schuster. The book explores the behind-the-scenes world of true crime television production.[4][9][10][2]
In 2026, St. Amant served as an executive producer on the true crime docuseries Killer Confessions: Case Files of a Texas Ranger, which premiered on Investigation Discovery on January 13, 2026, and became available for streaming on HBO Max the following day.[11] The series focuses on retired Texas Ranger James Holland and his interrogations of serial killers and other suspects, building on a segment St. Amant produced for 60 Minutes in 2019.[11][3][8]