Steven Shaffer has been charged in America with the very rare felony of “removing an object of antiquity” and will stand trial later this year, facing a possible five year sentence. Although such a charge generally involves a small item such as a goblet, this case concerns something significantly larger: an eight-ton boulder that Shaffer is accused of removing from the bottom of a river running between Kentucky and Ohio.

A huge piece of sandstone known as Indian Head Rock, the boulder was given that name because it has engraved on it a face that some experts have said is an ancient petroglyph (a rock carving) by a Native American. The boulder was registered at the University of Kentucky as a protected archaeological object. It was once used as a navigation marker on the river and historically became an attraction for local residents who would wade out into the river when the water was low in order to carve their initials on it. Most of it has been underwater since the 1920s.

In 2007, Shaffer, an historian, worked with a diving crew to float the boulder and tug it to the shore on his side of the river in Ohio. His crew then raised it from the water using a crane and drove it to a municipal building. Shaffer and the Ohioans say the rock is more relevant to their history than that of their neighbour state’s across the river, although Kentuckians disagree and have prosecuted in what is, in effect, a vexed custody battle over a hunk of history.

Shaffer’s trial has been scheduled for August and will need to resolve many intricate issues about the precise history and legal status of the rock. When the judge was told at a preliminary hearing that the full trial would be likely to last for weeks rather than days he said to the defence lawyer: “You’ve got to be kidding me?” The lawyer’s reply was essentially: if you think the rock is voluminous wait until you see the documentary evidence we need to bring to court.

The case might look straightforward but some of the boulder’s characteristics are not written in stone. One academic, for example, thinks that the face carving is not a prehistoric Native American work and is likely to have been executed with metal tools in the 19th-century.

An old philosophical conundrum asks what happens when an irresistible force meets an immovable object. That is an impossible question because it contains two contradictory ideas that cannot coexist. What happens, though, when the force of law sweeps over two intransigent states and an eight-ton boulder will be seen in the Indian Head Rock trial in the summer.

Professor Gary Slapper is Director of the Centre for Law at the Open University

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