Side-by-side comparison of the Statue of Liberty postage stamp mistakenly based on the scaled-down replica at the New York, New York Hotel in Las Vegas and the real statue. — Paul J. Richards/AFP/Getty Images

After 40 years at the U.S. Postal Service, the last 20 as head of stamp development, Terry McCaffrey has taken the credit or blame for the good, the great and the bungled. Until he retired at age 68 last December, he was responsible for the images on more than 2,500 American stamps. That number is more than half of all postage issued by the U.S. Postal Service since the very first stamp appeared in 1847.

Terry McCaffrey — Terry McCaffrey

See also: Starting a stamp collection.

Now that McCaffrey is retired, he's hoping to write a memoir of his time in the Washington office, which includes the latest post office "blunder" discovered earlier this year — the Statue of Liberty stamp.

Q. How did the photo of a replica instead of the actual Statue of Liberty recently find its way onto the "forever" stamp?

A. We were always looking for something patriotic and I searched through stock agency files. We've done many Lady Liberty stamps but we'd never done a tight close-up of her face, which is harder to find. Eighteen months ago I picked out one that made a strong visual symbol and we developed it. The stock agency had simply labeled it "Statue of Liberty." When it was issued last December, it alternated in a coil with the American flag. It wasn't until March that some eagle-eyed collector caught the mistake: We'd printed the face of a figure that stood in front of a Las Vegas casino instead of the real thing. If we'd known it wasn't the New York statue, we'd have chosen another photo, but we felt it was still a good stamp image. There's a billion out there we'd have to pull back from America's 33,000 post offices.

Q. Weren't there some other stamp errors on your watch?

A. A few. For example, some years ago, we issued a series of Legends of the American West stamps. Among others, we featured a black cowboy, Bill Pickett. The research department had cleared his dossier and declared that he had no heirs. After 184 panes of Bill Pickett's image had been sold, over 200 heirs were discovered. One of them called immediately. "This is not Bill Pickett. The picture on your stamp is that of his brother!"

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