Photo by SweetJen34.

WMATA asks individuals who use service animals on its rail, bus and MetroAccess services to keep them “under control at all times.” But what happens when there’s a dispute about what constitutes a service animal?

Today, a DCist reader shared this story from her morning commute:

This morning on a D6 bus heading west to Sibley Hospital, a bus driver would not let a woman onto the bus because he didn’t think that the dog she had with her was a service dog, despite her saying so and it wearing a vest that said “service dog.” Most troublesome is that when the bus driver closed the door on the woman and began to drive away, she held on to the front of the bus and ran alongside it, and the bus driver continued to drive. The driver must have seen that the dog was running along with her. She got in front of the bus, and the bus driver continued to drive. Passengers on the bus began to shout for him to stop. I recall hearing one woman at the front of the bus yell “This is terrible!” Everyone seemed genuinely worried that the bus driver was going to seriously hurt this woman or the animal.

Metro, however, tells a different story about what happened on that bus.

“The dog was a pit bull, and when the woman was informed that she could not board the bus with the pit bull, she stood in front of the bus blocking it from moving,” said WMATA spokesperson Ron Holzer. “All of the passengers then had to exit the bus and boarded the next bus. The police were called.” Neither the Metro Transit Police nor the Metropolitan Police Department had any additional comment on the incident. (A request for comment from the director of the city’s Office of Disability Rights, Derek Orr, is still pending — we’ll update if and when we hear back.)

Obviously, what happened in this scenario isn’t crystal clear, but it does bring up the interesting topic of pit bulls and their use as service animals — which is growing in popularity, even in areas where owning a pit bull is against the law. The Americans With Disabilities Act states that discrimination against the breed of any service dog is not permitted — and since not all service animals come equipped with licensing papers, it’s a legal requirement that businesses allow entrance to an animal wearing a “service animal” vest.

But there’s also a clause in the ADA that allows business people to exclude a service animal if it “poses a direct threat to the health or safety of others” or if the presence of the animal would “result in a fundamental alteration to the nature of the business.” Combine that with the stigmas associated with the breed, and we’re talking about one rather large gray area.