"From what I hear, it's not looking good for me," Rafferty wrote. "They're more concerned with hanging me than helping me."
The teen also wrote about his fear that decades in prison would mean that most of his loved ones would be dead by the time he got out.
"I talked to my lawyer. He says there's a chance I might be out by the time I'm 42," Rafferty wrote. "I know there is no way in hell that any kind of God would do that to me. I think about this, considering that all my meaningful family members would be dead, all my aunts and uncles, my grandmother and possibly my grandfather. You and mom would be dead or dying."
The mothers of both Beasley and Rafferty stand behind their sons.
Beasley's mother Carol Beasley, 70, told ABCNews.com that her son struggled to make ends meet as an unpaid chaplain and that he desperately did not want to go back to jail.
"Our family stands behind Richard," Beasley said. "He's always been a loving kid and a very giving person who cared about others. He spent hours helping people, praying over people that were dying … so many things."
Carol Beasley said that her son acted as a mentor for Rafferty and tried to get him interested in history, since the boy struggled in school after his parents' divorce.
Yvette Rafferty told "GMA" that her son was manipulated by Beasley and that he is innocent.
"I know one thing. My son told me that he didn't do it. And I believe it," Rafferty said. "There is a monster here. But it's not my son."
The first victim has been identified as David Pauley, 51, from Norfolk, Va., and the second victim as Timothy Kern, 47, of Massilon, Ohio.
On Tuesday, the Licking County Coroner's Office released a preliminary autopsy report for the third victim, whom they identified as John Doe, but noted on the report that he is "suspected" to be Ralph Geiger. The report said that the victim suffered a "penetrating GSW [gun shot wound] to head and injury to brain."
Beasley has an extensive criminal history and two Akron, Ohio, churches linked to Beasley have denied any direct connection to him.
Court records from Ohio show that Beasley had been in trouble with authorities as recently as February 2011 for charges including drug trafficking, aggravated menacing, tampering with evidence and possession of criminal tools.
Court documents from Texas show arrests and convictions for charges including burglary and the unauthorized use of a motor vehicle. Beasley spent about four years in prison in Texas.