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A 1925 article in The Boston Daily Globe featured a photo of a dog at a radio microphone for a special remote broadcast from a Pennsylvania prison.

He looks like a friendly, dark-haired Labrador. Two prison officers on either side have a hand on his back.

The caption says: This is Pep, "the pet dog Gov. Pinchot of Pennsylvania sentenced to Eastern State Penitentiary for life."

"He had killed the Governor's wife's cat," or so the story went, says Annie Anderson, the historic site researcher at Eastern State Penitentiary in Philadelphia — now a museum.

But there's more to the case of the canine convict who spent most of his life in Pennsylvania state prisons.

"There was this sort of production of sentencing Pep, the cat-murdering dog, to the prison," Anderson says.

Pep got his own inmate number and there's even a mugshot taken where he wears it around his neck.

He had arrived at an unusual, historic facility. It had been built to try a new way to reform offenders. Instead of medieval methods like the stocks or the ducking stool, Quaker reformists sentenced prisoners to reflect on their sins in solitary confinement and repent.

One hundred years later, with Eastern State much too crowded for that, Pep arrived as another experiment in modern prison reform.

A few years after his arrival, the governor's wife, Cornelia Pinchot, felt the need to clear the dog's name in an interview with The New York Times.

Cornelia "said that he had never killed her cat and that the family bred Labradors and he was just a gift to the prisoners to boost morale," Annie Anderson says.

In fact, Gov. Pinchot had already seen this done in Maine, so when he found himself with too many dogs at home, he decided to donate one to Eastern State.

You can imagine the guards jokingly taking a mugshot with their new prison pet. But why the newspapers? Why would they have repeated this story about the murdered cat?

That was all politics, says Dick Fulmer, who worked at Eastern State Penitentiary in the '60s and has spent years researching the facility's history.

He says the press at the time was very political and the Republican governor, known for palling around with President Teddy Roosevelt, was criticized for expanding government authority over state natural resources.

"The nasty, rotten reporters of the world, you know a couple of them, they got news of this going on and they published an article about how Gifford Pinchot, governor, wanted Pep sent to the prison," Fulmer says.

And so Pep, who actually wandered around the prison halls freely and became beloved by inmates and guards alike, got a fierce reputation.

This backstory is still told at the museum today, to add a little humor in a place with a long, dark history.

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