Martina McBride and her husband, celebrated recording engineer John McBride, are being sued over the way they allegedly treated unpaid interns who worked for their Nashville recording complex, Blackbird Studios.

Blackbird is one of the top recording studios in Nashville, serving as a recording home to a slate of multi-genre clients that includes Alabama, Ed Sheeran, the White Stripes and Taylor Swift, among others. According to Nashville's Tennessean newspaper, former Blackbird Studios Operations Manager Richard Hanson, who worked at the studio for five years, has filed a lawsuit against the couple, claiming that they have violated the law by mistreating unpaid interns who worked at Blackbird over the years.

Hanson's filing alleges that Martina and John McBride subjected their unpaid interns to unfair labor practices that included tearing down studio equipment, picking up groceries and takeout food and cleaning bathrooms. According to the Tennessean, one intern was even dispatched to the McBrides' home with a gun to check for a possible intruder, even though that intern had no experience with firearms.

According to his suit, the McBrides also yelled at interns for failing to perform the personal errands and duties that were not related to their job duties at the recording studio.

Hanson's complaint says the McBrides ignored him when he first voiced his concerns about their treatment of unpaid interns. When he then filed an official complaint with the state, he claims John McBride fired him an hour after he informed the couple, he claims. He is suing for $1 million, claiming that the McBrides violated the Fair Labor Standards Act in their treatment of unpaid interns. He is also asking for back pay, benefits, front pay and other damages. Hanson claims that because his firing was retribution for the complaint he filed with the state, it violated the Tennessee Public Protection Act

"It appeared that the primary beneficiaries of [the McBrides'] internship program were [the McBrides] rather than the unpaid interns," Hanson states in his lawsuit, according to the Tennessean. "Defendants made clear to [Hanson] that its unpaid internship program was a means to get free labor that it would otherwise have to pay employees to perform."

Martina McBride denied Hanson's claims in a statement to the Tennessean, saying, “Blackbird Studios cooperated with the Department of Labor and they found this claim was not supported by the facts. John and I have created a culture at Blackbird that is familial and supportive of everyone who walks through its doors.”

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