A double murder in the 1920s left one big question: Was Warren Lincoln insane?

In the weeks before a sensational 1925 murder trial, Dr. H.S. Hulbert reported that he was receiving threats as he prepared to counter the prosecution argument that Warren Lincoln was not mentally impaired when he killed his wife and her brother.

Lincoln, a lawyer and florist in Aurora, had confessed to the crime but pleaded not guilty by virtue of insanity. The Tribune had predicted that the trial would “be a battle of alienists,” using a term of the era for psychiatrists. The case evoked passions that embroiled even the men of science brought in to try to figure out a particularly enigmatic defendant.

Prosecutors had summoned analysts from the Elgin State Hospital for the Insane to the Aurora jail cell where Lincoln was held.

“For five hours yesterday, three experts on insanity talked with Warren Lincoln in an effort to determine whether the man who murdered his wife and brother-in-law, hacked off their heads, and then forgot whether he burned or buried their bodies, could be a candidate for the asylum or for the gallows,” the Tribune reported in January 1924, a year before the trial began.

Ultimately, the state decided Lincoln was sane, and that the gruesomeness of the crime was simply an effort to get away with it.

“It was no delirium,” a prosecutor said, “that caused this man to chop up the bodies of his victims, to place their heads in cement, it was to get rid of the evidence,” but instead was “A part of a perfect alibi plot.”

He noted that Lincoln sued his wife for divorce months after killing her.

“He wanted to get hold of property his wife and brother-in-law had,” the prosecutor said. “Also he owed his brother-in-law $1,600.”

Dr. Hulbert, however, was among those who supported Lincoln’s insanity plea. Another expert called by the defense was asked if he had any lingering doubts about his diagnosis.

“Absolutely not,” Dr A. B. T. Heym replied. “He was insane. The cold-blooded atrocity left no doubt.”

At trial, Lincoln was visibly upset by witnesses who said he was insane, and decided to take control of his defense. Scrapping the insanity plea, he invoked the so-called unwritten law of defending a family’s honor. As a lawyer, he should have known there is no such a thing: A husband isn’t legally entitled to kill a philandering wife.

Lincoln, his wife, Lina, and his brother-in-law, Byron Shoup, went missing in April 1924. Warren Lincoln turned up that June and claimed he had been kidnapped by his wife and Shoup, drugged, and forced to join a drug ring. He disappeared again that October before being arrested in January in Chicago.

He gave several versions of events , and at one point he cautioned reporters: “ Never mind what my story will be,” he said. “It hasn’t been told yet, and when I do tell it, it’ll be on the front page of the newspapers all over.”

Having fallen in love with the sound of his voice, Lincoln didn’t keep news junkies waiting. He spun tale after tale. Some were absurd, others mutually contradictory.

Among the unmistakably phony, as reported by the Tribune:

— “My brother-in-law told me my wife committed suicide. He said she did so because we suspected her of being unfaithful.”

— “Byron Shoup is alive and so is my wife. … She used to visit me long after the time the state says I killed her.”

— He did put two heads in concrete block, but they were not the heads of his wife and brother-in-law. He ran across them in the basement of his house.”

But the prosecution’s narratives, backed by a confession that provided the most credible version of events: rang true. Lincoln shot his wife and brother-in-law and decapitated them with a handsaw. He put their bodies in a greenhouse furnace. While watching them burn, he played solitaire on a nearby table. He then encased their heads in cement blocks.

The trial began Jan. 15, 1925, in a courtroom in west suburban Geneva.

“Upon the eve of the trial, Lincoln, who insists he was sane at the time of the murders, appeared smiling in his cell,” the Tribune reported. “He has gained weight while in jail and his complexion is rosy. ‘I was cruelly betrayed. That’s why I killed them.’”

The trial was still a box-office bonanza. “Hundreds who packed the courtroom and the courthouse corridors moved about restlessly”, the Alton Evening Telegraph reported. “Some of the more philosophical came long distances opened up lunches and fell to, much to the dismay of the bailiffs.”

Lincoln’s lawyers had announced “that the eccentric lawyer would not address the jury in his own behalf if they could prevent it. They said they had in mind the bizarre story he told from the witness stand.”

The lawyers still thought an insanity defense could save him from the gallows. And at one point a family member came to his defense, when Lincoln’s son told the jurors his father couldn’t be the murderer.

“I was in the greenhouse playing cards and my father slept with me there.“ John Lincoln testified. “And my father never burned any bodies in the greenhouse.”

The prosecutor countered by putting Lina Lincoln’s relatives on the stand. He underlined their pain with the details of Warren Lincoln’s cover-up of his wife’s murder.

“He put her head and that of her brother, Byron Shoup in cement,” the prosecutor said. “He found he did not have enough cement to cover them. He tried to push them down so that they would be covered forever and hidden forever. That’s how the skulls were fractured. He pounded and pounded until they were both covered.”

One Tribune story during the proceedings was headlined: “Lincoln jury views block, tomb of heads.”

When the jurors’ deliberations began, the courthouse consensus anticipated a guilty verdict and the death penalty.

When it proved to be life in prison, John Lincoln threw his arms around his father’s neck. Both shed tears of relief.

Warren Lincoln died in Stateville prison’s hospital in 1941.

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