Ratliff's body arrived at the State Medical Examiner's Office in Chapel Hill Wednesday morning. Durham investigators went to Bay City, Texas, Monday to exhume Ratliff, who died in November 1985 in Germany.
Ratliff, a former school teacher, was good friends with Mike Peterson and his first wife. Authorities say her body was found at the bottom of a staircase.
Ratliff's original autopsy report shows she died of a brain hemorrhage. It also says she had a scalp laceration as a result of the fall. There was no criminal investigation. Authorities say Mike Peterson was also the last known person to see Ratliff alive.
Kathleen Peterson died in December 2001. Her body was also found at the bottom of a staircase at the couple's Durham home. At first, the medical examiner called Peterson's death accidental, but another report found seven deep gashes to the back of the head.
Peterson, who has been charged in his wife's death, denies having anything to do with what happened to his wife and insists Ratliff died of natural causes. The district attorney says he is looking to see whether both deaths have any similarities.
Dr. Thomas Sporn, a forensic pathologist, explains even a body buried nearly two decades ago holds clues. He said pathologists will pay particular attention to certain things.
"Soft tissue changes, bone changes that might offer a different explanation of how Ms. Ratliff died," he said.
Sporn said officials will also look for any signs of trauma.
"You would see defects in the bones, assuming they are present, and those would be what we call fractures," he said.
Ratliff's two daughters, Margaret and Martha, have been raised by Peterson since their mother's death and consider him as a father to them. Although the daughters gave permission for their mother's exhumation, they wrote to the District Attorney's Office, saying they call the move appalling.
The autopsy is scheduled for Wednesday afternoon. Officials say it can typically take 4 to 9 weeks to get the results. Peterson's trial is scheduled to start May 5.
The judge in the case has yet to rule whether evidence obtained from the autopsy will be admissible in the trial.