Anderson (D) is an agent of the Federal Bureau of Investigation. D and other state and federal law enforcement officers conducted a warrantless search of the home of the Creighton family (P). The search was conducted because D believed that Vadaain Dixon, a man suspected of a bank robbery committed earlier that day, might be found there. He was not. Ps filed suit against D in a Minnesota state court, asserting among other things a claim for money damages under the Fourth Amendment. After removing the suit to Federal District Court, D filed a motion to dismiss or for summary judgment, arguing that the Bivens claim was barred by D's qualified immunity from civil damages liability. The District Court granted summary judgment on the ground that the search was lawful, holding that the undisputed facts revealed that D had had probable cause to search the P's home and that his failure to obtain a warrant was justified by the presence of exigent circumstances. Ps appealed to the Court of Appeals for the Eighth Circuit, which reversed. The Court of Appeals held that the issue of the lawfulness of the search could not properly be decided on summary judgment, because unresolved factual disputes made it impossible to determine as a matter of law that the warrantless search had been supported by probable cause and exigent circumstances. The Court of Appeals also held that D was not entitled to summary judgment on qualified immunity grounds since the right D was alleged to have violated - the right of persons to be protected from warrantless searches of their home unless the searching officers have probable cause and there are exigent circumstances - was clearly established. The Supreme Court granted certiorari.