Even though Bagley claims to be aware of “the basic rules of the craft of history” (xvi), he consistently violates them in Blood of the Prophets.
— W. Paul Reeve and Ardis E. Parshall, "review of Blood of the Prophets: Brigham Young and the Massacre at Mountain Meadows, by Will Bagley," Mormon Historical Studies (Spring 2003): 149.

Attempting to write a gripping story. Bagley exaggerates and sensationalizes the details beyond their actual significance. Throughout the entire book, facts associated with the massacre become crucial when tied to prophecy, omens, signs, oaths, patriarchal blessings, or temple rituals. Facts become extremely important if they are dark and dirty, have hidden meaning, or hint at some insidious secret, plot, or conspiracy. In addition, Bagley creates a melodrama characterizing the Mormons as sinister, evil, deceptive people, while the governor and Indian agents who cooperate with the Saints are weak, spineless dupes. The judges, military officers, and officials who challenge the Mormon theocracy he views as honorable, upright, respectable, courageous men.
—Lawrence Coates, "Review of Blood of the Prophets: Brigham Young and the Massacre at Mountain Meadows," Brigham Young University Studies 31 no. 1 (January 2003), 153–. off-site