SEATTLE — Photos showing a vendor selling service dog vests at the Washington State Fair caused a stir among the disability community recently. It raised concerns the products were being marketed to people whose pets aren’t actual service animals.

So what are the rules? And how do you know when someone’s companion is a legitimate service animal?

“Unfortunately, there’s no legal certification for a service dog, which is really frustrating,” said Emily Fruge, who trains service dogs.

Her son Grayson, age 9, has non-verbal autism and needs the assistance of his service dog Jack.

“He brings comfort, he brings safety, and now we can go anywhere with Grayson,” Fruge said.

Washington State law defines a service animal as one trained to perform tasks for the benefit of a person with a disability. Those tasks include assisting the blind, pulling a wheelchair, and alerting someone to the presence of allergens, among others.

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The Americans with Disabilities Act spells out that service animals are defined as dogs that are individually trained to do work or perform tasks for people with disabilities.

Becky Bishop, a trainer who owns Puppy Manners in Woodinville, says it’s difficult for business owners to verify if an animal is a service dog.

“It’s not a regulated service, so anybody can have a service dog or say they have a service dog and there’s no card, there’s no paperwork that you need to provide to them,” Bishop said.