In The Moon of Red Ponies - James Lee Burke

At the end of BITTERROOT, rodeo cowboy Wayne Dixon - 'the most dangerous, depraved, twisted and unpredictable human being I ever knew' - was sentenced to sixty years in Deer Lodge Pen for the murder of a biker in the Aryan Brotherhood.
Now, one year later, he's out, due to the DA's failure to disclose a piece of evidence.
Among his many crimes, Wayne once tried to bury alive Billy Bob's wife, Temple, a former-cop turned private investigator.
Dixon declares to Billy Bob that he's a reformed character - yessir! - and he needs his help in a venture to raise rodeo cattle.

Johnny American Horse, a possible descendent of Crazy Horse, whose worst offence till now has been the odd bout of drunkenness and a propensity to believe his dreams, is caught carrying a gun.
He tells Billy Bob he needs it for protection; in a dream he saw two men coming for him. Sure enough, those men in Johnny's dream are heading West, across the Great Plains to Montana, with Johnny as their target.
Johnny whets his hatchet and bowie knife and lies in wait; the assassins pitch up, and Johnny ensures that they will not present themselves to him again - 'at least, not outside the bright edges of his sleep.'
Now he's in serious trouble with only one man to whom he can turn - Billy Bob Holland.