Leibowitz, born in 1893, immigrated to the United States from Romania when he was four, attended college and law school at Cornell, then embarked on a career as a criminal defense attorney, seeing it as one path relatively open to Jews at the time. In the courtroom, Leibowitz was known for his meticulous preparation, knowledge of the law, vibrant voice, and flamboyant style.
Many people expressed surprise that the communists would ask Liebowitz to lead the Scottsboro defense. He was neither a communist or even a radical, but rather a mainstream Democrat who had never been associated with class-based causes. The choice of Leibowitz convinced many that the communists were serious about achieving justice for the Alabama defendants, and not just interested in making political hay. Leibowitz would be asked to accept as co-counsel, however, the ILD's chief attorney, Joseph Brodsky.
After reading the record of the first trials and becoming convinced of the innocense of the Scottsboro Boys, Leibowitz accepted the ILD's offer. He did so against the urgings of his wife and many friends who told him that the skin color of the defendants gave them no chance in the Alabama of the 1930's. He would work for the next four years on the cases without pay or reimbursement for most of his expenses.
Leibowitz quickly became an object of loathing around Decatur when he opened his defense of Haywood Patterson by challenging Alabama's exclusion of blacks from the jury rolls. Local hatred of Liebowitz grew uglier, as death threats were made against him after his tough cross-examination of Victoria Price. One national reporter overheard several people saying, "It'll be a wonder if he gets out of here alive." Five uniformed members of the National Guard were assigned to protect him during the trial, with another 150 available to defend against a possible lynch mob.
Leibowitz was stunned by the jury's guilty verdict in Patterson's 1933 trial. He compared the verdict to "the act of spitting on the tomb of Abraham Lincoln." Back in New York after the trial, Leibowitz vowed to defend the Boys "until hell freezes over." Speaking before enthusiatic audiences sometimes numbering in the thousands, he promised to take guilty verdicts to the Supreme Court and back until Alabama finally gives up: "It'll be a merry-go-round, and if some Klu Kluxer doesn't put a bullet through my head, I'll go right along until they let the passengers off." Leibowitz's determined efforts won the affection of his clients. Haywood Patterson said of Liebowitz, "I love him more than life itself."
After Judge Horton ordered a new trial for Patterson and the state transferred the cases to the courtroom of Judge William Callahan, Leibowitz's frustration grew. Virtually every motion or objection Leibowitz made was denied, virtually every motion or objection made by the prosecution was sustained. His anger showed, and Leibowitz found himself mocked, scolded, and reprimanded by the Judge Callahan. After guilty verdicts and death sentences were handed to Patterson and Norris, a battle for control of the case ensued between Leibowitz and the ILD. Liebowitz's anger with the ILD exploded after two ILD attorneys were charged with attempting to bribe Victoria Price.
Leibowitz appeared before the United States Supreme Court to participate in the appeal of Patterson's and Norris's convictions on the ground that blacks were systematically excluded from Alabama's juries. When Leibowitz alleged that the names of blacks appearing on jury rolls were fraudulently added after Haywood's trial began, Chief Justice Charles Evans Hughes asked Leibowitz if he could prove that allegation. Leibowitz called for a page to bring in the jury roll and a magnifying glass, which was passed from justice to justice. Their facial reactions indicated disgust. The Supreme Court reversed the convictions in a decision that Leibowitz called a "triumph for American justice."
After the third set of trials, Leibowitz began to involve himself again in projects unrelated to Scottsboro. He met on death row several times with Bruno Hauptmann, the German immigrant convicted of kidnapping Charles Lindbergh's baby, in the hopes of convincing him to reveal details of the crime.
In early 1937, following a series of secret meetings with Thomas Knight, Leibowitz reluctantly agreed to a compromise which would result in the release of four of the Scottsboro Boys while allowing prosecutions to again go forward against the others.Of the compromise, Leibowitz said, "I say yes, but with a heavy heart, and I feel very badly about it." In the next set of Scottsboro trials, Leibowitz allowed a local attorney to assume the more visible role, while he did the coaching. Leibowitz and others concerned with the Scottsboro Boy's welfare feared that the trials might become a refendum on Leibowitz himself, who was by then more unpopular than ever in northern Alabama.
After his work on the Scottsboro Boys case was finished, Leibowitz returned to his New York practice, then was appointed to serve as a justice on the Supreme Court of New York.
Leibowitz died in January, 1978.