A picture of a huge English mastiff that recently flew first class out of LAX went viral and triggered a new debate over what really defines a service dog.

The owner said that in this case, her dog, Hank, is legitimate because he detects her seizures.

But there are people out there who are abusing the service dog privilege, taking their animals everywhere and passing them off as service animals.

“It’s fraud, but it affects people like me,” said Lorri Bernson, who works with Guide Dogs of America and legally blind. She uses her dog Carter as her eyes.

“What defines a service dog is the task it’s trained to provide you,” she explained.

Guide Dogs of America breeds dogs, training them for up to two years before pairing them with someone. The dogs graduate classes, but there’s no documentation required proving service dog training.

The Americans with Disabilities Act mandates what questions a business can ask when a person enters with an animal.

“‘Is that your service dog? And what service is your dog trained to provide?,’” Bernson explained.

Bernson said, increasingly, some pet owners are avoiding those questions cosmetically, by outfitting pets with no training in service attire, so they can take them anywhere.

There are dozens of items anyone can buy online, essentially faking the appearance of a trained service animal.

“It causes more discrimination, in a way, against people like myself because the business owners are on higher alert,” Bernson said.

Jeff Trevathan said he trained his dog Cricket as a service animal to help him emotionally with PTSD and the physical impact of back surgery.

“She knows how much I weigh. I can place my hand on her and I can push myself up off the ground,” he said.

Trevathan said he’s been denied entrance to a Ralph’s grocery store location with Cricket.

“They would not recognize a pit bull as a service animal,” he said.

Responding to I-Team questions about Trevathan, a Ralph’s spokesperson wrote in an email that store policy on service animals follows the law but it’s a tough issue.

“If (a customer) they tell us it’s a comfort animal, we are required by law to not allow entrance. We work very hard to ensure customer safety, food safety and all applicable laws,” the statement read.

Trevathan recently entered the same Ralph’s location with Cricket and that time, no one asked any questions.

Bernson, who works with Guide Dogs of America, said pet owners who abuse the law simply to go places with a pet should walk in her shoes.

“I didn’t lose my vision so I could have my dog with me,” she said.

Bernson said the law was intended to give access to real service animals, not just ones that are cute.

Bernson also said that an untrained pet could act unpredictably, which could be dangerous for people and for real service animals.

She also said that even if you have a legitimate service animal, if it’s disruptive or aggressive — businesses have the right to demand that you leave.

“The ADA law is for people with disabilities, it’s not for dogs. It’s for people.”

For more information on disability rights, get California-specific laws here, and federal rules here.