In January of 2009, Scott Kimball provided authorities with a handwritten map to a location west of Vail Pass in Colorado. Investigators had to wait until the snow melted in June, but were able to locate the remains of Terry Kimball at the precise location Scott Kimball had drawn on his map.
Kimball was already in custody before his arrest on murder charges. In December 2008, he was sentenced to 48 years in prison on theft and habitual offender charges. At that time, the affidavit says he signed a "memorandum of understanding" that he would plead guilty to one count of second-degree murder, but be immune to further prosecution for other murders.
A condition of the memorandum was that Kimball lead authorities to the remains of Jennifer Marcum, LeAnn Emry, and Terry Kimball. Kaysi McLeod's remains had already been recovered without Kimball's help.
Catherine Olguin with the Boulder District Attorney's office told ABC News that she could not comment on why Kimball is being charged with two counts of second-degree murder given the memorandum of understanding. Prosecutors plan on holding a press conference after Kimball's arraignment Thursday.