The U.S. Department of Justice this week escalated the war of words in a fight over whether former federal prosecutor Peter Zeidenberg should be allowed to represent convicted ex-lobbyist Jack Abramoff.

During Zeidenberg’s time in the Justice Department, he prosecuted David Safavian, a government official nabbed in the Abramoff scandal. Zeidenberg, now a partner at Arent Fox, wasn’t part of the team that prosecuted Abramoff, but the Justice Department said the connection was close enough to potentially disqualify him from representing Abramoff now.