In United States v. Dunn (1987), the United States Supreme Court expanded the open fields doctrine. There, the court held that police officers may observe without a warrant items located inside constitutionally protected areas as long as the observation point itself is outside the curtilage, in an open field area not protected by the Fourth Amendment. (Dunn, supra, 480 U.S. at p. 304 [107 S. Ct. at p. 1141].) The court concluded that the officers in Dunn did not conduct an illegal warrantless search when they stood in an open field outside the curtilage and looked into the open door of a barn located inside the curtilage. (Ibid.) Similarly, in California v. Ciraolo (1986) 476 U.S. 207 [106 S. Ct. 1809, 90 L. Ed. 2d 210] (hereafter Ciraolo), the high court held that the fact that the area observed was inside the curtilage did not bar all police observation. (Id. at p. 213 [106 S. Ct. at pp. 1812-1813].) The court further held that warrantless observation of the cartilage area from an aircraft located in public navigable airspace was constitutionally permissible. (Id. at pp. 213-214 [106 S. Ct. at p. 1813].)