Usually on the attack in environmental cases, the U.S. government now finds itself the defendant in a lawsuit brought by a subsidiary of Texas-based oil giant ExxonMobil.

XTO Energy recently sued the U.S. Department of Justice in the U.S. District Court for the Middle District of Pennsylvania, seeking to have the agency turn over documents from its federal case involving environmental charges against it. XTO wants access to the documents to use in a separate criminal case brought against it by the state of Pennsylvania in which the state prosecutors are alleging it released toxic wastewater from a gas well site.

In its complaint, XTO states the challenged decision involves DOJ's refusal to produce documents in response to a valid state court subpoena duces tecum served by XTO upon the DOJ on Nov. 25, 2014.