William King Hale

Political cartoon depicting Mollie Burkhart and William Hale from the Enid Morning News Sunday edition on February 7, 1926

Hale was a segregationist and an influential member of the Democratic Party in Osage County.[11] He had considerable influence over the local Osage County prosecutor. During his election campaign, the prosecutor sought Hale's endorsement and after receiving it won every precinct near Hale's ranch. Hale used this connection to confer with local investigators during the initial investigation of Anna Brown's murder.[12] After Henry Roan's body was discovered, Hale accompanied the deputy and marshal to the ravine it was discovered in to recover the body.[13] Additionally, in 1921, Hale hired a private investigator to look into the murders. The investigator would later reveal to federal agents that he was hired to manufacture evidence and witnesses to "shape an alibi" for Hale and his accomplices, and not to solve the murders.[14] A Bureau of Investigation (BOI)[lower-alpha 3] report eventually concluded the chief of Ponca City Police, chief of Fairfax Police, Osage County prosecutor, and local Office of Indian Affairs agent were all under Hale's influence and would not be able to assist the investigation.[15]

The Osage Nation Tribal Council requested the Bureau of Investigation examine the murders. The Bureau sent undercover agents to investigate.[7] Investigators initially had trouble finding witnesses with Dick Gregg, a former member of the Al Spencer gang, being the only living witness. Gregg told investigators Hale had attempted to hire the Al Spencer gang to kill Bill and Rita Smith, but Spencer, the leader of the gang, had declined because killing a woman was "not my style." Gregg pointed investigators to Al Spencer, Henry Grammer, and Curley Johnson as having more information, but the three men were already dead. Eventually, a safecracker associated with Grammer named Asa Kirby as the bomber, but before agents could interview Kirby he was shot in a failed jewel heist. Investigators believed Hale had tipped both Kirby off of a shipment of diamonds and the store owner off as to a potential heist to orchestrate the killing. After this revelation, investigators began to believe Hale was potentially murdering witnesses, with some accusations he tampered with Grammer's car brakes and had poisoned Johnson.[16] Eventually, Burt Lawson, a man serving a prison sentence in McAlester, Oklahoma, came forward to testify he was instructed by Hale and Ernest Burkhart to plant the explosive device in the Smiths' home.[17] Hale generated additional suspicion when he brought suit to collect a life insurance policy for Henry Roan.[18] Hale had bought the life insurance policy in 1921; after his first application had been denied, he reapplied to a second life insurance company with a note signed by Roan certifying that Roan owed Hale $25,000 and was approved. When obtaining the required doctor's evaluation for the policy, Hale was asked by the doctor "Bill, what are you going to do, kill this Indian?" to which he responded "Hell yes."[19]

Agents were also tipped off when they realized the order and methods of the murders appeared to be done in a particular fashion to maximize Mollie's inheritance. For example, Anna Brown was murdered first after her divorce to insure that her inheritance went to family instead of their former partner, and Rita and Bill Smith were killed simultaneously in a bombing to trigger a simultaneous death clause in their will.[20]

William Hale in 1926 (second from the left) and John Ramsey (third from left) flanked by two U.S. marshals

A warrant for Hale and Ernest's arrest was issued on January 4, 1926 for the murders of Bill and Rita Smith. Ernest was apprehended immediately, but Hale could not be found. According to David Grann, Hale later turned himself in wearing "a perfectly pressed suit, shoes shined to a gleam, a felt hat, and an overcoat with his diamond-studded Masonic lodge pin fastened to the lapel." Hale maintained his innocence, so federal agents focused on interrogating Ernest; he broke and turned state's evidence after being confronted with outlaw Blackie Thompson (who had been in state custody for murdering a police officer) willing to testify Ernest tried to hire him to do the killings.[21] When confronted with Ernest's testimony, Hale maintained his innocence.[22]

The Department of Justice wanted Hale to be tried in federal court, fearing his potential influence over Oklahoma state courts; however, a federal judge ruled the killing, which took place on an unalienated allotment, fell under the jurisdiction of Oklahoma courts. Hale legal counsel included former attorney general of Oklahoma Sargent Prentiss Freeling.[23] The case was moved to state court and his first hearing was March 12. According to David Grann, he recited a poem to his supporters in the courtroom saying

Judge Not! The clouds of seeming guilt may dim thy brother's fame

For Fate may throw suspicion's shade upon the brightest name.[24]

While under trial in 1926, Hale sold his ranch to the Drummond family and the Mullendores family. The ranch land was later broken up and sold to smaller ranchers.[25]

Hale was tried alongside John Ramsey in July 1926 for the murder of Henry Roan in federal court (after the United States Supreme Court case United States v. Ramsey (1926) held that federal courts had jurisdiction) in Guthrie, Oklahoma.[26] By the time of their first trial, Ernest Burkhart had been sentenced to life imprisonment in Oklahoma courts.[4] The jury began deliberations on August 20 and five days later Hale and Ramsey's first trial resulted in a hung jury.[27] After the first trial, several witnesses were tried, indicted and convicted for taking bribes or giving threatened testimony. Hale and Ramsey's second trial was scheduled for late October.[28] The trial was transferred to Oklahoma City. Ernest testified that Hale paid Ramsey a new Ford and $500 to kill Roan. Hale denied the allegations, and claimed to be in Fort Worth at a livestock show during the bombing at the Smiths' house and that he had no reason to want Roan dead.[4] Jury deliberations began on October 28, and the next morning the jury found them both guilty of first-degree murder and sentenced them to life in prison.[29] Hale appealed and was retried. The case was retried in federal court in Guthrie, Oklahoma, but ended in another hung jury. The next trial in Oklahoma City resulted in another guilty sentence, this time for 99 years. Hale appealed to the United States Court of Appeals for the Eighth Circuit and a new trial was ordered. Hale was tried a final time in federal court at Pawhuska, Oklahoma.[4]

He was convicted in federal court on October 29, 1929, for the murder of Henry Roan, and sent to the Leavenworth Penitentiary in Kansas.[7] The warden during his stay was Tom White, the man who had headed the investigation into the Osage Indian murders.[30] There he worked in the tuberculosis ward and on a prison farm.[31] During his sentence he never admitted to the murders, and a psychological evaluator noted "he has put behind him any feeling of shame or repentance he may have had."[32]

• David Grann's 2017 book Killers of the Flower Moon reports Hale as mastermind of murders with detailed evidence.[34]
• In the 2023 film Killers of the Flower Moon, directed by Martin Scorsese, Hale was portrayed by actor Robert De Niro.[34]