The U.S. Department of Transportation might soon allow exotic pets to fly on planes, so long as they are used as service animals, or to provide emotional or psychiatric support to their owners, reports Fox News.

According to the Daily Mail, the proposed new rule is part of a draft manual on equality for people with disabilities who fly commercial airlines. Under it, animals like pot-bellied pigs, miniature horses and monkeys would be allowed on commercial flights provided they fit the above criteria.

However, carriers don't have to admit "unusual" animals like ferrets, rodents, spiders, snakes and other reptiles, reports CNS News.

CNS also reports that with the new rule, published in the DOT's “Nondiscrimination on the Basis of Disability in Air Travel: Draft Technical Assistance Manual,” airlines may ask for verification as to whether an animal is allowed on board if there is a "reasonable basis for questioning."

But, "if you determine that the pot-bellied pig is a service animal, you must permit the service animal to accompany the passenger to her seat provided the animal does not obstruct the aisle or present any safety issues and the animal is behaving appropriately in a public setting,” it says.

Fox adds that other passengers' complaints don't weigh in the matter: "The DOT said that is not a legitimate complaint and that airlines cannot deny a passenger with a disability 'because an animal may offend or annoy persons traveling,' the proposed regulation states."

Passengers with animals do, however, have to provide proof that the animal won't need to relieve itself in-flight, or can do so in a way that's not a sanitation issue.

Concerns have been raised that these new rules may make it easier for people to cheat the system. Apparently, as Fox notes, there have been cases of passengers going through the motions of outfitting their dogs as service animals so they can fly free in the cabin.

Singer Aubrey O'Day took some heat last month after she provided a doctors note, which apparently allowed her "emotional support animals" to fly with her. At least one writer questioned the nature of her "mental illness," and asked whether she is giving mental illness a bad name.

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