In U.S. v. Dunn (1987) 480 U.S. 294, the U.S. 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.) 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.) The factors to be examined in determining whether an individual reasonably may expect the area in question should be treated as the home are: "the proximity of the area claimed to be curtilage to the home, whether the area is included within an enclosure surrounding the home, the nature of the uses to which the area is put, and the steps taken by the resident to protect the area from observation by people passing by." (Dunn, supra, 480 U.S. 294, 301.)