Later courts have limited "Erie" slightly, to create a few situations where United States federal courts are permitted to create federal common law rules without express statutory authority, for example, where a federal rule of decision is necessary to protect uniquely federal interests, such as foreign affairs, or financial instruments issued by the federal government. "See, e.g.", "Clearfield Trust Co. v. United States", (giving federal courts the authority to fashion common law rules with respect to issues of federal power, in this case negotiable instruments backed by the federal government); "see also" "International News Service v. Associated Press", 248 U.S. 215 (1918) (creating a cause of action for misappropriation of "hot news" that lacks any statutory grounding); "but see National Basketball Association v. Motorola, Inc.", 105 F.3d 841, 843–44, 853 (2d Cir. 1997) (noting continued vitality of "INS" "hot news" tort under New York state law, but leaving open the question of whether it survives under federal law). Except on Constitutional issues, Congress is free to legislatively overrule federal courts' common law.