Does Ms. Landowner own the airspace over her property up to the minimal level for safe flight as set by federal regulations?

With rapid technological advances, the law cannot ignore the privacy interest of citizens. If drones were allowed to invade private property without permission, all previous assurances of privacy would be eliminated.

While the concept of trespass-by-drone may be relatively new, the principle is merely an extension of well-established law. Trespass is not limited to the surface of the land. Instead, trespass can occur underground or up into the airspace above a landowner’s property.

Although courts have applied this concept more commonly to low-flying manned aircraft, these rules should also apply to drone aircraft.

Washington has long recognized that the realities of our modern world have eliminated that property ownership extends up indefinitely:

It is ancient doctrine that at common law ownership of the land extended to the periphery of the universe-Cujus est solum ejus est usque ad coelum. But that doctrine has no place in the modern world. The air is a public highway, as Congress has declared. Were that not true, every transcontinental flight would subject the operator to countless trespass suits. Common sense revolts at the idea. To recognize such private claims to the airspace would clog these highways, seriously interfere with their control and development in the public interest, and transfer into private ownership that to which only the public has a just claim. 

Cheskov v. Port of Seattle, 55 Wn.2d 416, 421-22, 348 P.2d 673, 676-77 (1960).

The Supreme Court of the United States has made this principle clear. In United States v. Causby, the Court noted:

[I]f the landowner is to have full enjoyment of the land, he must have exclusive control of the immediate reaches of the enveloping atmosphere. Otherwise buildings could not be erected, trees could not be planted, and even fences could not be run. The principle is recognized when the law gives a remedy in case overhanging structures are erected on adjoining land. The landowner owns at least as much of the space above the ground as he can occupy or use in connection with the land. 

United States v. Causby, 328 U.S. 256, 66 S.Ct. 1066 (1946).

Although Washington’s Supreme Court examined the issue of how far up this “envelope extended,” ultimately, the Court found that the public domain began above the minimum safe altitudes of flight prescribed by the Civil Aeronautics Authority. See Ackerman v. Port of Seattle, 55 Wn.2d 400, 410-411, 348 P.2d 664 (1960).

Accordingly, at least for the purposes of trespass, trespass would lie for anyone to enter into the airspace over a property below the “minimum safe altitudes of flight.”

So, what happens when Mr. Neighbor admits that he took photographs of the airspace above Ms. Landowner’s land by a drone aircraft? These drone flights would constitute a trespass as the drone violated the airspace owned by Ms. Landowner.

Generally speaking, Washington has adopted the definition of trespass contained in the Restatement (Second) of Torts, which provides that “One is subject to liability to another for trespass, irrespective of whether he thereby causes harm to any legally protected interest of the other, if he intentionally (a) enters land in the possession of the other, or causes a thing or a third person to do so, or (b) remains on the land, or (c) fails to remove from the land a thing, which he is under a duty to remove.”

In this case, Mr. Neighbor either (a) caused a thing to enter into Ms. Landowner’s airspace, and/or (b) entered into the airspace himself.


With advancements in technology come numerous threats to privacy. If the law provides no actual consequences for such invasions, then the law provides no deterrent from future trespasses.

Mr. Neighbor apparently believed he could get around the rules of trespass by flying a drone above Ms. Landowner’s property. However, as stated above, Ms. Landowner owns this airspace. As such, even the flight of a drone over this property constitutes trespass.