Gary is an environmental and energy lawyer who lives and works in Washington, D.C. He co-chairs the Energy Industry Group at the law firm of Covington & Burling working with technology and clean energy leaders. 

He was appointed by President Obama and served, with Senate confirmation, as Deputy Director of the White House Council on Environmental Quality. Gary helped develop and guide the Obama Administration’s environmental, public health, and clean energy agenda, including spearheading negotiations that achieved the Administration’s historic agreement to double motor vehicle fuel efficiency standards and significantly cut greenhouse gas emissions with the support of automobile manufacturers, states, labor unions, environmental and consumer groups, and Congress. 

Gary also served, upon Presidential appointment and Senate confirmation, as the General Counsel of the U.S. Environmental Protection Agency and Counselor to the EPA Administrator during the Clinton Administration. While there, Gary led efforts to protect children’s environmental health, and authored climate change opinions that were ratified by the U.S. Supreme Court in its landmark decision finding that greenhouse gases are pollutants under federal law. 

Gary has worked to protect public lands from the Everglades to Alaska, and currently leads litigation against the Trump Administration's efforts to dismantle Grand Staircase Escalante National Monument. Gary chairs the Board of Directors of the Rock Creek Conservancy in Washington, D.C., and serves on the Advisory Boards of Cornell's Center for Sustainable Global Enterprise and of the Center for Applied Environmental Law and Policy.  He has also served as an Adjunct Professor at the Georgetown University Law Center.

Gary attended Cornell Law and began his legal career working for revered Cornell grad Honorable Elbert Tuttle of the U.S. Court of Appeals in Atlanta. He is married and lives with his wife Sherry, an Assistant U.S. Attorney. He visits his Cornell grad daughter, a playwright and dramaturge in London, and his son, an aspiring journalist in Hanoi, and he still pursues his Ithaca-induced loves of bicycling and cross-country skiing.