This story has also been updated to correctly identify Grossi as the recipient of the letter. Initial reports had characterized the comments made by Engler's attorney as directed at Nessel.

Former Michigan State Interim President John Engler is refusing to sit for an interview with Michigan Attorney General Dana Nessel's investigators unless Assistant Attorney General Christina Grossi recuses herself from the office's investigation into MSU, according to a letter obtained by the Detroit Free Press.

In a Tuesday letter to Chair of the MSU Board of Trustees Dianne Byrum, Nessel claimed her office had agreed to travel to interview Engler "contingent on Mr. Engler being unavailable to interview in the State of Michigan." However, she learned from media reports that Engler had attended a home basketball game in East Lansing March 9. In the letter, Nessel asked MSU to compel Engler to appear in Lansing within the next two weeks.

"Mr. Engler's conduct is troubling in several respects," Nessel wrote in the letter. "In addition to our concern that Mr. Engler might be attempting to manipulate the forum of his interview to insulate himself from the repercussions of it, I am equally concerned about the message this sends to both the Nassar survivors and the community-at-large."

In a statement, Byrum said she was unaware Nessel's office had not been able to meet with Engler.

"I agree with the AG’s position that Engler should honor the request to meet and cooperate fully," Byrum's statement reads. "The Board will review Engler’s contract and determine what actions on our part will help facilitate an interview.”

However, in a Wednesday letter to Grossi obtained by the Free Press, Engler's attorney Seth Waxman maintains he never claimed Engler would not travel to Michigan. In the letter, Waxman refers to Grossi's characterizations of Engler as "libelous" and calls her actions "prosecutorial misconduct."

Prior to the dispute, Engler was scheduled to interview with Nessel's office March 28 in Washington D.C., according to the letters.

Nessel's office is seeking to speak with Engler about his role in the university's response to the Larry Nassar cases, as well as his knowledge related to allegations that former MSU Trustee George Perles resigned "in exchange for the forgiveness of a debt he owed," according to Nessel's letter.