given Weingarten actual authority to make the trades, SHB should bear no responsibility for the margin call. Peltz was at least equally culpable with SHB for creating the short position. Thus, SHB is not liable because in pari delicto potior est conditio defendewtis: when there is mutual wrongdoing, the law favors the defending party. See Bateman Eichler, Hill Richards, Inc. v. Berner, 472 U.S. 299, 306, 105 S.Ct. 2622, 2626-27, 86 L.Ed.2d 215 (1985). The in pari delicto defense is used sparingly, and is narrowly defined in litigation under federal regulatory statutes. See Perma Life Mufflers, Inc. v. International Parts Corp., 392 U.S. 134, 145, 88 S.Ct. 1981, 1987-88, 20 L.Ed.2d 982 (1968) (not recognizing defense in antitrust action); Ross v. Bolton, 904 F.2d 819, 824 (2d Cir.1990) (<HOLDING>). To ensure-that the defense is narrowly
recognizing a duty of best execution under federal securities law recognizing defense in securities case holding that morrison precludes securities claims brought by us investors who purchase securities on a foreign exchange even where those securities are also listed on a us exchange recognizing the incorporation by reference doctrine in a securities case recognizing an innocent possession defense though the defense in that case is more properly considered a justification defense as life and limb were arguably at stake