Wiegand earned her Bachelor of Arts, cum laude, from Princeton University in 1997, and her Juris Doctor, cum laude, from Cornell Law School in 2000, where she served as an Articles Editor of the Cornell Law Review.

[2] Upon graduating from law school, Wiegand became an associate at Arnold & Porter in Washington, D.C., where her practice focused on antitrust matters.

She later served as a law clerk to Judge D. Brooks Smith of the United States Court of Appeals for the Third Circuit.

Wiegand previously served as the Deputy Chief of the Office's Civil Division, and thereafter served in the Criminal Division's Major Crimes Unit, where she prosecuted a variety of crimes, including large-scale drug trafficking, child exploitation, illegal firearms, and fraud.

President Trump nominated Wiegand to the seat vacated by Judge Peter J. Phipps, who was elevated to the United States Court of Appeals for the Third Circuit on July 22, 2019.