Peterson, a former Bolingbrook police sergeant, was found guilty of murder in the death of his ex-wife, Kathleen Savio. He remains the primary suspect in the disappearance of his fourth wife, Stacy Peterson.
"Prison is all the nighmarish things that one would think," Peterson writes. "I'm in a cell the size of a broom closet, peeling paint, rusting fixtures, I have no TV or anything and I haven't been out since I got here. The food is terrible and I'm again in solitary confinement."
Peterson's letters reveal that he fears being killed by other inmates or even the guards.
FOX 32's Craig Wall spoke to Kathleen Savio's sister Sue Doman for his TV report. When told about his letters, she said she has no sympathy for Peterso and just wishes he would die.