March 18, 2025
US 10th Circuit Court of Appeals
131 F.4th 1153 (10th Cir. 2025) (click for full text of opinion)
The Tenth Circuit Court of Appeals ruled that a federal law on access for public lands preempted Wyoming’s trespass law in relation to “corner crossing”—the act of stepping from one parcel of public land to another at their common corner without physically touching the private land below.
The dispute involves a “checkerboard” pattern of land ownership in Wyoming’s Carbon County, where alternating one-square-mile sections of public land are surrounded by privately owned land, created by 19th-century land grants to railroads. A private ranch owner (Iron Bar), sued a group of hunters for civil trespass that had “corner-crossed” to access BLM land for elk hunting. Iron Bar argued that this act, while not involving physical contact with the ground, was a trespass on the airspace above their property.
At issue was whether the Unlawful Inclosures Act (UIA) of 1885, a federal law, preempted Wyoming’s state common law of trespass. Iron Bar contended that the hunters’ actions were a trespass under Wyoming law, which grants a landowner rights to the airspace above their property, and that the UIA did not override this right. Conversely, the hunters argued that the UIA protects their right to access public lands, and any state law that effectively blocks this access is preempted.
The Tenth Circuit Court of Appeals affirmed the lower court’s decision in favor of the hunters. The court held that while corner crossing might be considered a trespass under Wyoming’s state law, the UIA explicitly prohibits landowners from “inclosing” public lands, which includes actions that obstruct “free passage or transit over” public lands.
The court reasoned that Iron Bar’s attempt to use its airspace rights to prevent corner crossing was, in effect, a form of an unlawful inclosure. By creating a barrier to access, Iron Bar was functionally landlocking public lands, which the UIA was specifically designed to prevent.
