Zachary Adams is charged with first-degree murder and especially aggravated kidnapping in the case, although Bobo's body has not been found. Adams was charged in March, nearly three years after the young woman's disappearance from her home near Parsons in Decatur County.
Authorities have yet to disclose a motive.
The last person to see Bobo was her brother, who told authorities he saw a man in hunting clothes leading her into the woods around the family's home on April 13, 2011.
The TBI says it will announce a new development in the case on Tuesday afternoon.