NEW YORK — (CNN) Today is National Doughnut Day. Or, if you’re a police officer, Christmas.

Indeed, like a Dalmatian to a firefighter, doughnuts have been so closely associated with cops that it’s become a trope.

Movies propagate it — from “Police Academy” to “Wreck-It Ralph.”

The public peddles it — such as, when demonstrators dangled donuts in front of officers during an Occupy Wall Street rally.

And sometimes police themselves perpetuate it, such as the Chicago cop who allegedly accepted a $5,000 bribe — stuffed in a doughnut bag.

But behind every stereotype, there’s usually an ounce of truth. So we set out to seek how this one came about.

The love goes way back

“It’s not an urban legend,” says Michael Krondl. He would know; he literally wrote the book on this topic, namely “The Donut: History, Recipes and Lore.”

The cops-doughnut love affair was in full bloom even before the 1950s.

At the time, cops working the graveyard shift didn’t have much choice when they wanted to take a break.

There were the all-night diners. But the food took too long.

And then there were the doughnut shops. They opened early to get ready for the morning crowd. And a cop could walk in, get a coffee (staying awake is important in fighting crime) and a doughnut to wash off the aftertaste.

But there was one more draw, Krondl says.

“A lot of times, young women were working behind the counter.”

Turning punchlines into headlines

Which brings us to today. Officers have more choices. And also, they’re way more health conscious.

So, understandably, some are bothered by the stereotype. We asked police down in Atlanta about it, but a spokesman politely declined to talk about it.

But others have embraced it.

In Illinois, officers climb rooftops at Dunkin Donuts every year to raise money for Special Olympics.

In Portland, Oregon, when weed became legal, police issued a tongue-in-cheek visual aid to show how much is legally acceptable to carry. They shaped the weed into doughnuts.

And in Michigan, when a local doughnut shop was on the verge of closing, officers pooled their money and bought it. They called it — what else — Cops and Doughnuts. Today, you can buy a “Don’t Glaze me, Bro” T-shirt there and munch on a “Misdemeanor Wiener.”

So if you run into an officer today, don’t be afraid to share the Doughnut Day love and offer them a warm, sugary glazed one. Especially if they’re writing you a ticket.

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