On Saturday, what John Williams thought was going to be an easy afternoon manning a booth at a local gun show in Evansville, Indiana, turned into something much more unpleasant. The retired Army sergeant first class was kicked out of a gun show on Feb. 4 because of his service dog.

Williams, a 43-year-old Iraq War vet, was slated to be an exhibitor at the show before organizer Thomas Allman asked him to leave because of his dog allergy, local NBC news affiliate WFIE reported on Feb. 5.

Williams told Task & Purpose that he set up his booth and went to his vehicle to get his dog. He was then waved down by Allman, who said that dogs weren’t allowed there because he was allergic.

“He said ‘I'll let you get set up, and when I get sick, I'm gonna sue you,’” Williams told WFIE.

However, according to the Americans with Disabilities Act, a dog allergy isn't sufficient grounds to ban a service dog.

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Williams' service dog WinchesterPhoto via Soldier Dogs for Independence Facebook

“Allergies and fear of dogs are not valid reasons for denying access or refusing service to people using service animals,” a 2010 Department of Justice fact sheet about service animals reads. “When a person who is allergic to dog dander and a person who uses a service animal must spend time in the same room or facility, for example, in a school classroom or at a homeless shelter, they both should be accommodated by assigning them, if possible, to different locations within the room or different rooms in the facility.”

Williams, who is a board member of the nonprofit service-dog organization Soldier Dogs for Independence and is trained in dealing with these kinds of tense scenarios, said his first priority was deescalating the situation. He said he took Winchester to his vehicle, then tried to re-engage Allman in a constructive manner. He said he reminded Allman of basic information about service dogs, like their need to be well-groomed (for reasons precisely like this one), and asked if there were any accommodations that could be made to make the situation work.

But instead of trying to meet him halfway, Allman offered him $50 and asked him to leave, Williams told Task & Purpose. Allman also threatened to sue Williams.

Williams said he waited in the building lobby until a total of seven police officers arrived on the scene, at which point the authorities took statements from both sides. Williams said the gun show staff told police that “since it was their gun show, they could not allow dogs,” despite the fact that the event was held at a National Guard armory and the organizers’ are required to adhere to state and federal laws.

“It doesn't apply because he's not setting up at my gun show because we don't allow dogs in my gun show,” Allman told WFIE.

According to a police incident report provided to Task & Purpose, Allman’s wife and business partner, Karen Sue Allman, told Williams that she would refund his booth rental and setup costs, and let him attend the event.

“Williams agreed to leave soon, after quietly protesting in the entryway, and deal with the situation thru proper legal channels more familiar with the American Disabilities Act,” the report states.

Williams has required the use of a service dog since he retired from the Army in 2012.

“I didn’t leave my house for the first year or so after I retired from the military,” Williams told Task & Purpose, “because when you’re in the military, then you can surround yourself with people who’ve been in the same situations you’ve been in, and you’re comfortable with that. When you finally get out of that shell and then you go someplace and get denied like this, it just kinda sets you back.”

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John WilliamsCourtesy photo

Williams said that right after his military retirement in October 2012, a constellation of personal catastrophes struck, including financial issues, the dissolution of a relationship and the death of his 11-year-old dog.

“I really thought the sky was falling in on me,” he said.

Williams’ mom, who lived in Evansville, Indiana, told him about a program called Soldier Dogs for Independence, which matches veterans with service dogs. He wound up moving to Evansville, and within a week, his VA disability claim came through and he signed up for the program. Winchester acts as “a bracing dog” for him, so he’s used like a cane. He says he took the public-access test (through which dogs get certified as service animals) about eight months later.

Winchester also helps with Williams’ pulmonary sarcoidosis, a condition that causes his knees and ankles to flare up, which he developed as a result of his service in Iraq.

As of press time, Williams said that he and his girlfriend are “fairly certain” they’ll pursue legal recourse against the gun-show organizers.

“One of our advocates is the Indiana Bar Association, so the legal consideration is definitely there, and we’re leaning that way,” Williams said. “The absolute first concern is gonna be ensuring that all of this gentleman’s events that are held in armories are in compliance.”

Task & Purpose reached out to Allman who refused to comment for this story.

The show in question was sponsored by the Tri-State Knife and Gun Collectors LLC and held at the National Guard Armory in Evansville, Indiana.