Dennis Rader, known as the BTK (“bind, torture, kill”) serial killer, has written a letter from prison stating that he is going to cooperate with author Katherine Ramsland on an upcoming book about his murders, the Wichita Eagle reported. In a statement to the Eagle, Ramsland, a forensic psychology professor at DeSales University in Pennsylvania, said, “I’m trying to make this a serious effort that will have some benefit for people who study this kind of crime.”

Several families of the ten victims Rader killed in an area near Wichita, Kansas sued him for wrongful death after his arrest and incarceration in 2005. Kansas statutes stipulate that any profits derived by persons convicted of crimes who sell their story must go to a victims’ fund, and in Rader’s letter, he explained that he signed over media rights to the families of his victims. James Thomson, one of the lawyers who represented most of Raders’ victims families, told the New York Times that a percentage of profits from Ramsland’s book will go to the families. Rader wrote that his main reason for cooperating is to compensate the families of his victims. He also wrote that criminologists would benefit: “People like me, need to be under stood [sic],” he wrote. “That would be my way helping debt to society [sic].”

Among Rader’s ten victims over the span of 30 years were a 9-year-old boy, a 62-year-old woman, and a 38-year-old man. Rader was known for sending letters to police and newspapers taunting them for not catching him, signed “BTK.”

Stephen King’s novella “Full Dark, No Star,” inspired by Rader’s killing spree, has been made into a feature length film starring Joan Allen and Anthony LaPaglia. The adaptation, titled “A Good Marriage,” opens in theaters Friday. The storyline, involving a wife who discovers her husband is a serial killer, angered Rader’s daughter Kerri Rawson, who told The Wichita Eagle that there was no way her mother could have known her husband was a killer. Ms. Rawson insisted she and her family did not find out about Rader’s murders until after he was arrested, and further accused King of “exploiting my father’s 10 victims and their families.”

Rader is serving ten consecutive life sentences at El Dorado Correctional Facility in Kansas. Although Ramsland does not yet have a publisher, according to Rader, “the long work on a book is close to a deal.”