The U.S. Department of Justice has joined a lawsuit charging that the University of Michigan at Ann Arbor’s football stadium violates the Americans With Disabilities Act.

The motion to intervene was filed on Tuesday in federal court in Detroit after the U.S. Department of Education, which had been investigating the stadium, referred the case to the Justice Department for litigation. The lawsuit is Michigan Paralyzed Veterans of America v. University of Michigan.

Michigan Stadium, known as “The Big House,” was built in 1927 and seats 107,501 people. According to the Education Department, the stadium offers only 88 seats for people with disabilities.

In late October, the Education Department sent a 42-page letter to the university stating that Michigan was violating the ADA and the Rehabilitation Act of 1973.

The investigation concluded, among other things, that the football stadium lacked sufficient seating for patrons in wheelchairs, that the accessible seats were not dispersed around the stadium, and that the stadium provided no wheelchair-accessible toilets.

Michigan has not admitted any wrongdoing in the case. The university has said that renovations of the stadium that began on Monday will triple the number of wheelchair-accessible seats. —Libby Sander