This is a story about identity drift. Not identity theft — we did not steal Emma G.’s identity. It came drifting over, like snow drifting across an empty parking lot. The problem was that once her identity had drifted to us, we had a hard time giving it back.

First came an envelope addressed to someone we’d never heard of — call her Emma G. — with a yellow post office forwarding sticker printed with our address. We handed it back to the mail carrier.