Ingham County Prosecutor Carol Siemon requested a special prosecuting attorney from Michigan Attorney General Dana Nessel's office Monday, Press Secretary Ryan Jarvi confirmed in an email. Hughes said this was due to O'Brien's long-term professional acquaintance with Ingham County Prosecutor's Office.

Jarvi said in the email that the attorney general's office is reviewing the request and after the initial review is complete, it may assign an assistant attorney general to the case or work with the Assistant Attorneys Coordinating Council to place the case with another prosecutor.

As a detective, O'Brien was involved in a 2014 Title IX investigation into now convicted ex-MSU doctor Larry Nassar's sexual abuse. O’Brien was assigned to survivor Amanda Thomashow’s case but cleared Nassar of Thomashow's report of sexual abuse.

Ingham County Assistant Prosecutor Debra Rousseau said in a 2018 report that O’Brien failed to “consult additional experts, despite being asked to do so.”

After over a year on paid administrative leave, O'Brien was demoted from the assistant chief at MSUPD to captain. She returned to duty on Sept. 8, 2020, as a captain for special projects after being on hiatus since April 2019. Her husband, former MSUPD Detective JJ Bradac was placed on leave on Feb. 1, 2019. He is no longer employed at the university or MSUPD.

After O'Brien's 2014 investigation, MSUPD submitted a warrant for criminal sexual conduct. Prosecutors declined charges.