The Pennsylvania Department of Environmental Protection has made the rare move of enlisting a ­lawyer from outside the agency—and, even more unusually, from outside the state—to argue an environmental case before the Pennsylvania Supreme Court.

The agency has hired veteran Washington, D.C., litigator Jonathan S. Massey—whose resume includes representing former Vice President Al Gore in the 2000 Florida ­election litigation—to handle its appeal from a Commonwealth Court ruling in EQT Production v. Department of Environmental Protection.