Her handcuffed hands in her lap, Lisa Griggs of the Deschutes County Sheriff’s Office sat in the lobby of the Red Robin in Bend on Saturday afternoon, grinning gamely as patrons filled a jar with cash and checks.

As the jar filled slowly — the sign balanced on her knees said she’d stay locked up until she raised $500 — Griggs bantered with customers, many of whom were amused or just puzzled by the sight of a uniformed officer in handcuffs.

“How much to keep her locked up?” joked a man waiting to be seated.

“Did you get in trouble for stealing fries?” asked a wide-eyed young boy.

Volunteers from the Deschutes County Sheriff’s Office and the Bend Police Department joined officers from around the state at all 17 Oregon Red Robin locations Saturday for “Tip-A-Cop,” a fundraiser for Special Olympics Oregon.

Officers in uniform worked side by side with restaurant staff, filling drinks, clearing tables and even singing the Red Robin happy birthday song in exchange for donations from customers.

Project coordinator Laura Conard said the event causes some confusion, with some patrons finding it hard to believe she’s a “real sheriff” and not a restaurant employee who somehow got her hands on a sheriff’s uniform.

Not all diners are equally excited to see an officer approaching their table, Conard said.

“We do recognize some of our customers, but they’re generally pretty cordial about it,” she said.

Conard said the restaurant had been busy and patrons generous for most of the day, putting them roughly on target to match last year’s haul of $9,000 in donations.

Manager Simon Taylor said most of the officers on duty Saturday could probably make it as full-time members of the Red Robin crew if they’re interested in a career change. Seeing the officers smiling and joking with customers is fun for everybody at the restaurant, he said.

“So often you see law enforcement on your bumper, it’s more of a separation,” Taylor said. “Here, you get to talk to them and interact with them, which is great.”

Faith Wiles said the “wicked observation skills” she’s honed as a detective with the Bend Police Department translate well to restaurant work, allowing her to spot empty drinks and patrons getting ready to leave from across the room. Still, the pace is hectic, and often she finds her herself racing to keep up with the Red Robin crew.

“The people who really deserve props are the customers donating to Special Olympics, and the employees who let us come in and get in the way and take part of their tips for a good cause, and we really appreciate that,” Wiles said.