When you can’t change the truth, you go after its traces. The government can turn thousands of deaths into a single number: “Several thousand people were killed.” A number has no voice, no address; you can build a story around it, close a case, turn a page and move on.

But “So-and-so, born in such-and-such a year, killed on such-and-such a date, buried in such-and-such a plot” is no longer a number; it is evidence. A person—by name and face and address. And this is exactly what the government fears: that the crime will come out of the realm of an ambiguous story and find an address.

A grave gives coordinates to a crime, a name gives the victim an identity, a date gives death a place in time, and a gravestone keeps all of it, like a document, in its proper place. The government says: “It’s over. Forget it.” The gravestone says: “No. Here lies someone you killed.”

That’s why they go back to the gravestone—not just out of spite, but out of the fear of a killer who thought that by burying the body, the crime scene would also be buried; yet some clue still remains on the ground.