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.

The case centers on whether Pennsylvania's Clean Streams Law ­authorizes the DEP to issue ongoing penalties against companies for the continued presence of pollutants in state waters. In January, a three-judge panel of the Commonwealth Court unanimously ruled that the DEP did not have that ­authority, letting plaintiff EQT Production, a natural gas producer, off the hook for potentially millions of dollars in ongoing penalties ­related to pollution caused by fracking leaks.