In a suit by a former police officer against the city that employed him and certain police officers, alleging racial discrimination and disparate treatment in his suspension and ultimate firing, summary judgment in favor of the defendants on all claims is affirmed, where: 1) the law of the case doctrine did not preclude summary judgment, as nothing in the Second Circuit's previous opinion in the case controlled the district court's rulings being appealed; 2) the suspension without pay pending an investigation into the plaintiff's criminal conduct was not an adverse employment action under the circumstances; and 3) the plaintiff had no constitutionally recognized cause of action for deprivation of "professional courtesy" that police sometimes extend to their fellow officers.