zellner also notes, mr. kratz has no qualifications that would allow him to diagnose mr.. kratz, who prosecuted both steven avery and brendan dassey, says he's undaunted. >> are you afraid of kathleen zellner? >> no. i'm not involved in the case anymore. i shouldn't be afraid of anything. my involvement -- >> she could unravel your work if what she's saying has some weight to it. you don't think she has a chance? >> i don't. >> she's so confident. why are you so confident? >> because we spent 18 months pug is cetogether. it wasn't just thrown together. it wasn't a bunch of keystone cops. it was done very professionally, very well. >> kratz does have personal regrets. in his book, he admits to past prescription drug abuse and says he's ashamed that he sent sexual texts to a domestic violence victim two years after avery's trial. a scandal which led to his resignation. while he still takes issue with "making a murderer," he says he's moving on with a new life and a new girlfriend. >> i'm hoping this book will change the narrative. >> meanwhile, avery continues to fight and