Eaton County District Judge Julie Reincke ruled Monday.
Authorities say Simon knew in 2014 that Nassar had been accused of molesting a patient at a campus clinic. But Simon told police she knew only that a complaint had been filed against a sports doctor.
Nassar sexually assaulted his patients for decades. Simon is charged with two felonies and two misdemeanors.
The ruling came after it was disclosed that Michigan State trustee Nancy Schlichting resigned Saturday over the governing board's decision to drop a promised independent investigation into the handling of complaints against Nassar.
Schlichting, who was appointed less than a year ago, says she could no longer serve after the board wouldn't proceed with the review.