Professor Breckenridge specializes in environmental and natural resources law. She began her career as an attorney with the Environmental Protection Agency in Washington, DC, where she worked on some of the agency's initial regulatory efforts to implement the Clean Water Act, the Safe Drinking Water Act and the Surface Mining Control and Reclamation Act. Professor Breckenridge continued her environmental work as an assistant attorney general with the state of Tennessee and the commonwealth of Massachusetts. She served as a law clerk for Judge Gilbert S. Merritt on the US Court of Appeals for the Sixth Circuit in 1977-1978.

Before joining the faculty of the School of Law, Professor Breckenridge was chief of the Environmental Protection Division for the Massachusetts Attorney General's Office, where she was engaged in a wide range of litigation to enforce the requirements of federal and state air and water pollution statutes, hazardous waste management requirements, and wetlands and tidelands protection laws.

At Northeastern, Professor Breckenridge teaches courses in environmental law, wildlife and ecosystems law, land use zoning and planning law, Property. She also works with students on independent study projects focusing on a variety of related topics, such as urban environmental justice, affordable housing and federal lands management. In her research and advocacy work, she has a particular interest in aquatic ecosystems and in the evolution of property and regulatory systems to manage conflicts over water flow and quality. As a member of the board of directors of the Charles River Watershed Association and a participant in other government task forces, she has advocated for new policies and regulations to manage urban infrastructure and land uses in order to maintain adequate water quality and instream water flows in rivers and streams.