Sara Nelson said it's up to the Department of Transportation to establish policies to crack down on fake service animals.
She said flight attendants are getting bitten, legitimate service animals are being attacked and animals are defecating on airplanes.
She called the number of emotional support animals on airplanes a "safety and security issue."
"It’s pretty clear to us that fraud is being committed here, that people are fraudulently saying these are emotional support animals," Nelson said.
In January, Delta Airlines announced it transports 700 service or support animals daily on planes and it's seen an 84 percent increase in incidents involving animals on airplanes since 2016.
As a result, it announced new policies rolling out Thursday for emotional support animals.
Nelson said a key point of Delta's policy is that passengers must sign a document that their animal is trained, and if the animal acts out, Delta can hold the passenger accountable.
"I think the fact that Delta has put forward policy shows there is a real need for increased enforcement, increased oversight," Nelson said.
In 2015, the FOX31 Problem Solvers exposed two Colorado companies -- National Service Animal Registry and its partner Chilhowee Psychological Services -- showing how easy it was to buy an emotional support animal certification.
One counselor lost his license as a result of the story, but the company stayed in business.
After an online survey and two brief phone calls, a FOX31 producer obtained an emotional support animal certification for her cat.
The letter came from counselor Jerry Snodgrass, who is based in Oregon and who works with Chilhowee Psychological Services.
The letter stated he was treating the producer for a mental health disability and she can fly with her cat.
Neither Chilhowee Psychological Services nor National Service Animal Registry responded to a request for an interview.
However, Snodgrass did speak over the phone.
"We don't do this just so people can fly with their animals," Snodgass said.
He said he does a thorough job screening people before deciding if they need an emotional support animal.
He pointed the finger at other online companies who he said advertise that passengers are guaranteed a certification by simply paying for it online.
He also said it's up to passengers to be honest about the reasons they want to fly with their pets.
"I don't think we are adding to or creating the problem. I just can't make that connection," Snodgrass said.
Nelson said at this point, it's tough to tackle online sales so she said it's up to the Department of Transportation to implement policies to crack down.
She believes it will act quickly.
"We need to have defined rules by the Department of Transportation that provides a consistency across the airline industry," Nelson said.
"I think they are very concerned that if they don't act, the needs of those that need the help of service animals will be interrupted."
Along with Delta Airlines, other airlines are rolling out new policies for emotional support animals.
United announced starting Thursday, it'll requires additional documentation for passengers traveling with emotional support animals.
