I'm referring to the two confessional autobiographies by John D. Lee (convicted for his part in the Mountain Meadows Massacre) and Wild Bill Hickman, who confessed to several murders but was never convicted. Do historians give any weight to these claims?
Links to full text of their books:
https://archive.org/details/mormonismunveile00leej
http://www.salamandersociety.com/library/brighams_destroying_angel-william_a_hickman.pdf