Robert Clay Allison was a Presbyterian minister's son who became one of the most fearsome gunfighters of the American Old West. This deep dive strips away Hollywood mythology to trace his timeline and examine how frontier justice actually operated in a lawless vacuum.

From a Civil War medical discharge tied to a head injury to vigilante violence in New Mexico, Allison exploited the legal definition of self-defense again and again. We separate documented facts from the self-serving PR campaigns of famous lawmen and reveal his surprisingly ordinary death.

• How a possible brain injury may explain his volatile impulse control
• The gruesome Charles Kennedy lynching and severed-head display
• The deadly dinner-table duel with professional killer Chunk Colbert
• Why Wyatt Earp's famous showdown story was likely fabrica ...