[6] At the time of the murder, he had completed an undergraduate degree at the University of Chicago with Phi Beta Kappa honors and planned to begin studies at Harvard Law School after a trip to Europe.

Though Leopold and Loeb knew each other casually while growing up, they began to see more of each other in the spring of 1920;[17] their relationship flourished at the University of Chicago, as part of a mutual friend group.

[19] When Loeb met Leopold the pair began to steal things together, and worked out a system to cheat their friends and family during games of bridge, though it was largely unsuccessful.

[19] They also upgraded to larger crimes, including breaking into people's homes to steal things like wine, piano benches and vacuum cleaners.

As he explained to a psychiatrist: “Making up my mind to commit murder was practically the same as making up my mind whether or not I should eat pie for supper, whether it would give me pleasure or not.”[19] Leopold was also interested in Friedrich Nietzsche's concept of "supermen" (Übermenschen), interpreting them as transcendent individuals possessing extraordinary and unusual capabilities, whose superior intellects allowed them to rise above the laws and rules that bound the unimportant, average populace.

[7] Leopold believed it was possible that he and Loeb could become such individuals, and as such, by his interpretation of Nietzsche's doctrines, they were not bound by any of society's normal ethics or rules.

[7] In a letter to Loeb, he wrote, "A superman ... is, on account of certain superior qualities inherent in him, exempted from the ordinary laws which govern men.

[24] On the afternoon of May 21, 1924, using an automobile that Leopold rented under the name Morton D. Ballard, they offered Franks a ride as he walked home from school.

The precise sequence of the events that followed remains in dispute, but a preponderance of opinion placed Leopold behind the wheel of the car while Loeb sat in the back seat.

[26] With the body on the floor of the back seat, out of view, the men drove to their predetermined dumping spot near Wolf Lake, in the extreme south side of Chicago.

After mailing the typed ransom note and burning Franks' clothes, then cleaning the blood stains from the rented vehicle's upholstery, they spent the remainder of the evening playing cards.

[36] They asserted that on the night of the murder, they had picked up two women in Chicago using Leopold's car, then dropped them off some time later near a golf course without learning their last names.

While it was generally assumed that the men's defense would be based on a plea of not guilty by reason of insanity, Darrow concluded that a jury trial would almost certainly end in conviction and the death penalty.

[47] Thus, he elected to enter a plea of guilty, hoping to convince Cook County Circuit Court Judge John R. Caverly to impose sentences of life imprisonment.

The defense presented extensive psychiatric testimony in an effort to establish mitigating circumstances, including physical abnormalities, an over-abundance of money and, in Leopold's case, sexual abuse by a governess.

[54] Its principal arguments were that the methods and punishments of the American justice system were inhumane, and the youth and immaturity of the accused:[17][55][56] We read of killing one hundred thousand men in a day [during World War I]; probably exaggerated, but what of it?

It will be easy today, but in Chicago, and reaching out over the length and breadth of the land, more and more fathers and mothers, the humane, the kind and the hopeful, who are gaining an understanding and asking questions not only about these poor boys, but about their own.

[57] Darrow's handling of the law as defense counsel has been criticized for hiding psychiatric expert testimony that conflicted with his polemical goals and for relying on an absolute denial of free will, one of the principles legitimizing all criminal punishment.

Leopold was transferred to Stateville Penitentiary in 1925 for an appendectomy, where he worked in the shoe factory and then in the library as a clerk for the prison's Protestant chaplain.

[61] On January 28, 1936, Loeb was attacked with a straight razor in a shower room by his fellow inmate James Day; he died in the prison hospital soon afterward.

[62] Though several prison officials including the Warden believed that Loeb had been murdered, Day was found not guilty by a jury after a short trial in June 1936.

[61] In the early 1950s, author Meyer Levin, a graduate of the University of Chicago, requested Leopold's cooperation in the writing of a novel that was based on the murder of Franks.

Levin portrayed Leopold, under the pseudonym Judd Steiner, as a brilliant but a deeply disturbed teenager, psychologically driven to kill because of his abnormal sexuality, troubled childhood and an obsession with Loeb.

[79] In 1959, Leopold sought to block production of the film version of Compulsion on the grounds that Levin's book had invaded his privacy, defamed him, profited from his life story and "intermingled fact and fiction to such an extent that they were indistinguishable.

"[77][80] After 11 years and many appeals, the Illinois Supreme Court ruled against him,[81] holding that Leopold, as the confessed perpetrator of the "crime of the century," could not reasonably argue that any book had injured his reputation.

Judge Ángel M. Umpierre presided over the wedding at a civil ceremony, which was held at the Brethren Service Project in Castañer, Puerto Rico.

He also worked for an urban renewal and housing agency, and he conducted studies on leprosy at the University of Puerto Rico School of Medicine.

[21] Never the Sinner, John Logan's 1985 play,[89] was based on contemporary newspaper accounts of the case, and included an overt portrayal of Leopold and Loeb's sexual relationship.

[91] In his book Murder Most Queer (2014), theater scholar Jordan Schildcrout examines changing attitudes toward homosexuality in various theatrical and cinematic representations of the Leopold and Loeb case.

[92] Other works said to be influenced by the case include Richard Wright's 1940 novel Native Son,[93] the Columbo episode "Columbo Goes to College" (1990),[94] Tom Kalin's 1992 film Swoon,[95] Michael Haneke's 1997 Austrian film Funny Games and the 2008 International remake,[96] Barbet Schroeder's Murder by Numbers (2002),[97] Daniel Clowes's 2005 graphic novel Ice Haven,[98] the Murdoch Mysteries episode "Big Murderer on Campus", Stephen Dolginoff's 2005 off-Broadway musical Thrill Me: The Leopold and Loeb Story,[99] Micah Nemerever's These Violent Delights (2020)[100] and the Ghostface killers in Scream (1996).