William McBoyle stole an airplane, and it was perfectly legal. Just to be clear, he actually took possession of someone else’s aircraft without their permission and never gave it back. Even so, no law was broken. For purposes of further clarification, McBoyle was not a government agent, repossession specialist or anything like that. He was, in everyday language, a common thief. The rightful owner of the airplane was upset and pressed charges, but it was all for naught, because what McBoyle did was not against the law. If you have trouble believing this, all you have to do is check with the U.S. Supreme Court, and you will find it was in full agreement with the legality of the situation.

To add a bit of context to this, let us take you back to the incident. It happened in 1926, when William McBoyle paid an associate to steal a plane and fly it from Ottawa, Illinois to Guymon, Oklahoma. Along the way, the airplane crashed and was destroyed, but that fact does not play into the legality of this criminal operation.

McBoyle was charged with violation of the National Motor Vehicle Theft Act, in that he stole a motor vehicle and transported it across state lines. This made it a federal offense.

The facts were not in dispute. What was in contention, however, was whether the law applied in this case. McBoyle maintained that an airplane was not a motor vehicle. If it wasn’t a motor vehicle, he couldn’t properly be convicted of stealing one.

The argument may seem silly to you, but it went all the way to the United States Supreme Court. The Supreme Court has wrestled with such weighty matters as whether a tomato is a fruit and whether a person has to be able to walk the entire course to be considered a golfer. Now it was being asked to determine whether an airplane is a motor vehicle.

After much consideration, the Court issued its opinion in McBoyle v. United States, 283 U.S. 25 (1931). Justice Oliver Wendell Holmes wrote the Court’s conclusion that McBoyle was not guilty of the charges against him because, in fact, an airplane was not a motor vehicle, at least as then defined by federal law.

The Court concluded:

Although it is not likely that a criminal will carefully consider the text of the law before he murders or steals, it is reasonable that a fair warning should be given to the world in language that the common world will understand, of what the law intends to do if a certain line is passed. To make the warning fair, so far as possible the line should be clear.

McBoyle went free. Of course, having crashed the plane, he didn’t exactly profit from his crime. Also, Congress immediately got to work and amended federal law to make it clear that a airplanes are considered motor vehicles, just in case any wise guy tried to pull off the same stunt in the future. For a brief period of time, however, there was a burgeoning market in the United States for anyone who wanted to legally steal an airplane.

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