FairMormon is a non-profit organization dedicated to providing well-documented answers to criticisms of LDS doctrine, belief and practice.
Criticism of Mormonism/Books/Blood of the Prophets: Brigham Young and the Massacre at Mountain Meadows/Chapter 12
Response to claims made in "Chapter 12: I Have Slain My Children"
A FairMormon Analysis of: Blood of the Prophets: Brigham Young and the Massacre at Mountain Meadows, a work by author: Will Bagley
Response to claims made in Blood of the Prophets, "Chapter 12: I Have Slain My Children"
Jump to Subtopic:
The author claims to have found another source by John D. Lee, upon which he relies.
Author's sources: "Discursive remarks," anonymous manuscript in Utah State Historical Society archives. [ATTENTION!]
"Anonymous sources are usually worthless....Blood of the Prophets...spends several pages with the "Discursive Remarks,"...[and] attributes the work to John D. Lee, as if another Lee account can be trusted." 
- Robert D. Crockett, "A Trial Lawyer Reviews Will Bagley's Blood of the Prophets," FARMS Review 15/2 (2003): 199–254. off-site