Wanted: The World’s Sweetest Grandma

They once were on the walls of every post office in the U.S. You could live in the smallest, most bucolic town, and there they were: malevolent-looking men wanted for the most dastardly crimes, glaring right at you. Scowling men, scarred-up men, stone-faced men, sneering men—a jarring sight on a pleasant summer afternoon, especially if you were tagging along with your mom or dad.

Just as ominous as the cold-eyed faces on the posters was the sight of the men’s smudgy fingerprints—not that families buying stamps had any idea what they were supposed to do with those prints.

In the pre-internet, pre-email days, the neighborhood post office was a regular stop for just about every American family. Law enforcement knew that if they wanted the public to be on the lookout for criminals on the lam, the most efficient way to publicize those lawbreaking faces was via post offices. The FBI in Washington constantly mailed those film-noir-worthy posters to every post office in the land.

No more. The wanted posters began to disappear years ago with no ballyhoo. For a while they were moved to binders chained to tables in post-office lobbies; today, by a directive deep inside the Postal Operations Manual (subsection 125.343), local postmasters are advised that wanted posters must be kept behind the counter, and shown to the public only upon request.

Post office walls today are reserved for merchandising—the Postal Service needs all the revenue it can lure. There are still more than 31,000 USPS offices in the country, but people are not mailing letters with the frequency they once did. Between 2000 and today, the annual volume of first-class mail has dropped by more than 50 billion pieces.

Law enforcement has found other ways to get criminals’ mugs in front of the public: websites, electronic billboards, social media.

The FBI’s most-wanted list now has its own Twitter and Instagram accounts, but the competition for the public’s attention is fierce. The FBI’s most-wanted list has some 146,000 Twitter followers, while Taylor Swift has almost 92 million.

For those of us who remember the wanted posters in post offices, the walls today can look kind of bland. As I left the lobby in Berkeley, I glanced over at where the face of a snarling desperado once might have been. I saw instead a pink-and-white greeting card for sale, perfect for mailing to the world’s sweetest grandma.

Mr. Greene’s books include “Chevrolet Summers, Dairy Queen Nights.”