The question whether congressmen have standing in federal court to challenge the lawfulness of actions of the executive was answered, at least in large part, in the Supreme Court's recent decision in Raines v. Byrd , 521 U.S. 811 (1997). Raines involved a constitutional challenge to the President's authority under the short-lived Line Item Veto Act. Individual congressmen claimed that under that Act a President could veto (unconstitutionally) only part of a law and thereby diminish the institutional power of Congress. Observing it had never held that congressmen have standing to assert an institutional injury as against the executive, see id. at 821, the Court held that petitioners in the case lacked 'legislative standing' to challenge the Act.
The Court noted that it had found standing for a congressman in Powell v. McCormack , 395 U.S. 486 (1969), where he was unconstitutionally excluded from Congress, thus depriving him of a salary and the House seat he was constitutionally due, both personal injuries. The Court did not decide whether congressmen would have standing to challenge actions of Congress, which diminished their institutional role. Cf. Michel v. Anderson, 14 F.3d 623 (D.C. Cir. 1994) (congressmen ...