Hayes pleaded not guilty last month to murder and "accessory after the fact of murder" charges, almost two months after a jury found her husband, Grant Hayes, guilty of first-degree murder in the killing and dismemberment of Ackerson - who was the mother of his two oldest children.
Grant Hayes blamed Amanda for actually killing Ackerson - saying he only helped dispose of the body.
Hayes - aka Grant Haze - was charged - along with Amanda - with murdering the 27-year-old at their Raleigh apartment in July, 2011 during a long-running custody dispute. Prosecutors say they chopped up Ackerson's body, put it in coolers, and then drove them in a rented U-Haul to Amanda Hayes' sister's house in Richmond, Texas, where the body parts were dumped in a nearby creek.
Court documents obtained by ABC11 Monday revealed that Amanda Hayes' attorney, Johnny Gaskins, petitioned the court to take custody of the SUV the couple allegedly drove to Texas for 48 hours to examine it.
Gaskins received the silver 2009 Dodge Durango on Saturday and returned it to the Raleigh Police Department Monday before noon.
Following the inspection, Gaskins filed a motion that stated while he had the SUV he found " ... a physical item that is critical to the defendant's ability to properly and adequately defend herself at trial."Gaskins also wrote, "It appears that the officers of the Raleigh Police Department and the State of North Carolina failed to recognize the item for what it was."
He claimed to have secured the item in a sealed container and is now asking for permission to have it tested. It is unclear what the object is.
The DA would not comment Monday. The next step is to have the allegations of "new evidence" authenticated at Amanda Hayes' hearing on Thursday.
Amanda Hayes' trial is set for Jan. 20.
Grant Hayes is currently serving a life sentence in prison.