EL PASO, Texas -

There's an old cliche about cops and donut shops.

This weekend, some El Paso police officers are embracing the branding. But they're putting a twist on that stereotype -- and it's all for charity.

Roberto Cardenas has a vested interest in the customer traffic at the Krispy Kreme donut shop in West El Paso. He's not a manager. He's not even an employee. He's a cop. But he's not gazing longingly at the glazed delicacies through the glass case. He's on the roof.

"Cops on top of donut shops -- well, it's a good attention-getter," said Cardenas, with a large grin on his face. "You're up on the roof and you yell at somebody. And they're wondering where it's coming from and once they know why you're here, they're eager to help."

The El Paso police sergeant is raising money for the Special Olympics by camping out on the hot roof of the donut shop, using a tent to shield himself from the sun.

"We started this morning at 6 am and we'll be here until 6pm on Sunday," Cardenas said.

Aside from raising money with his fellow law enforcement officers, he knows how he'll be spending the rest of his time.

"I'm just standing up there and looking around being a people watcher. That's pretty much all you can do up there on the roof," said Cardenas.

The money raised will benefit the estimated 3,000 athletes who participate in the Special Olympics in El Paso.