a heavy burden to succeed in such an endeavor.” Microfinancial, Inc. v. Premier Holidays Internat’l, Inc., 385 F.3d 72

litigation in deference to parallel criminal proceedings is discretionary. . . . A movant must carry a heavy burden to succeed in such an endeavor.” Microfinancial, Inc. v. Premier Holidays Internat’l, Inc., 385 F.3d 72, 77 (1st Cir. 2004) (citations omitted). When a defendant facing possible criminal liability invok