Killers of the Flower Moon: The Osage Murders and the Birth of the FBI by David Grann:
He and his friend didn’t divulge anything. But two witnesses revealed that on the day Lewis disappeared, they had seen, a few miles from her houseboat, a car heading toward a snake-infested swamp. On January 18, 1919, investigators, with their pant legs rolled up, began to comb the thicket of vegetation. A reporter said that one of the lawmen had “scarcely stepped in the water of the bayou when his feet struggled for freedom. When he reached to the bottom to disengage them he brought up a thick growth of woman’s hair.” Leg bones were dredged up next. Then came a human trunk and a skull, which looked as if it had been beaten with a heavy metal object. GREWSOME FIND ENDS QUEST FOR MARY LEWIS, a headline in the local newspaper said.
Middleton’s companion confessed to beating Lewis over the head with a hammer. The plot was conceived by Middleton: after Lewis was killed, the plan was to use a female associate to impersonate her so that the friends could collect the headright payments. (This strategy was not unique—bogus heirs were a common problem. After Bill Smith died in the house explosion, the government initially feard that a relative claiming to be his heir was an impostor.) In 1919, Middleton was convicted of murder and condemned to die. “There was a point in Mary’s family that they were relieved the ordeal was over,” Jefferson wrote. “However, the feeling of satisfaction would be followed by disbelief and anger.” Middleton’s sentence was commuted to life. Then, after he had served only six and a half years, he was pardoned by the governor of Texas; Middleton had a girlfriend, and Lewis’s family believed that she had bribed authorities. “The murderer had gotten only a slap on the hand,” Jefferson wrote.