As chief legal officer, Littleton leads a department of approximately 230 lawyers along with legal and claims professionals. She oversees all legal matters related to regulatory proceedings, commercial transactions, litigation, labor, employment, the environment, benefits, cyber, privacy and customer claims. As corporate secretary, Littleton also leads the corporate-governance function.

Littleton was responsible for the transactional work and regulatory approvals required for the spin-off of Exelon’s generation and retail businesses in 2022. She negotiated the buy-back of Électricité de France S.A’s interest in Constellation Energy Nuclear Group, which owned interest in several of Exelon’s nuclear plants. Littleton also led the company’s response to Commonwealth Edison’s deferred prosecution agreement, including related Department of Justice and Securities and Exchange Commission investigations, regulatory proceedings, and securities, consumer-fraud, and derivative litigation.

Littleton is a member of the Exelon Foundation Board of Directors. She also is the executive sponsor of The Forum for Executive Women and the Network of Exelon Women. 

Active in the greater Chicago community and nationally, Littleton co-chairs the Chicago General Counsel Forum and is on the Board of Directors of the Illinois Holocaust Museum and the Lincoln Park Zoo. She is a member of the Association of General Counsel, the Edison Electric Institute’s General Counsel Forum, the Economic Club of Chicago, Cornell Law School Dean’s Advisory Council, and the Stetson University College of Arts & Sciences Advisory Board. Littleton also is active with Legal Counsel for Legal Diversity and has made the organization’s Leaders-on-the-Front pledge.

Littleton received her law degree, magna cum laude, from Cornell Law School and her Bachelor of Arts degree from Stetson University.