A tire shop tasked with performing an inspection on a limousine that crashed and killed 20 people in upstate New York last year allegedly falsified maintenance records for the vehicle, according to the district attorney.

A former employee for a Mavis Discount Tire branch alleged that he never performed a brake service on the limousine but the shop submitted the invoice for the service in order to meet a sales quota, according to a letter from the Schoharie County District Attorney.

The letter states that Virgil Parks worked at Mavis and purchased a brake cylinder to install in the Prestige Limo vehicle on May 4, 2018, but later learned from another employee the part was never replaced in the limousine.

“In addition, Mr. Parks told us that he did not perform the DMV inspection of the limousine but gave Mr. Klingman the NYS DMV inspector certification card he needed for the inspection,” the DA's letter said.

Parks was terminated by Mavis in February, according to the district attorney's letter.

A spokesperson for Mavis disputed the allegations Wednesday night, calling the claims "inaccurate or misleading."

"Mavis is committed to providing high quality, safe, affordable services to our customers. Our service and billing policies are honest, fair and sound and we vehemently disagree with any allegations to the contrary," the statement said. "Mr. Hussain and his criminal defense lawyers are attempting to falsely attack Mavis in a desperate diversion tactic to shift responsibility away from Mr. Hussain, where it solely belongs."

The limo crashed in October of last year while transporting a group of friends celebrating a birthday, killing all 18 inside as well as two pedestrians. Nauman Hussain, who ran Prestige Limousine, was charged with criminally negligent homicide after the crash.

Hussain's attorney Joseph Tacopina submitted the letter from the district attorney to the court Tuesday, claiming that Parks' account exonerates Hussain.

"Stated otherwise, Mavis's fraudulent conduct — not anything undertaken by defendant Nauman Hussain — was the true legal cause of the accident," Hussain's attorney wrote.

Federal safety records obtained by NBC News after the crash in 2018 indicated that Prestige Limo had multiple safety violation citations, including having "brakes out of service."

The "brakes out of service" citation, issued after a March 21 inspection, indicated that 20 percent or more of the roughly 5-ton vehicle's stopping power was compromised.

Prestige Limo also had at least one other vehicle with inspection red flags, including brake system concerns and worn tires, federal records show. The records indicate 22 violations this year for the company's 3-vehicle fleet.