Although To Kill a Mockingbird is a work of fiction, the rape trial of Tom Robinson at the center of the plot is based on several real trials of Black men accused of violent crimes that took place during the years before Lee wrote her book. Lee does not exaggerate the racism in her account. If anything, she downplays it: unlike many Black defendants from the time period, Tom has a competent defense lawyer who believes in his innocence, and he is able to escape lynching by a mob. One lesser-known trial that likely contributed to the novel was a murder case in which Harper Lee’s father, a lawyer named A.C. Lee, participated. A.C. Lee defended Frank and Brown Ezell, a Black father and son accused of murder, but they were found guilty and executed by hanging. A.C. Lee never tried another criminal case, and there is speculation that Lee’s novel was influenced by her father’s experience with the racism of the judicial system. 

To Kill a Mockingbird also reflects the Scottsboro Boys trial, one of the best-known cases of the 1930s. In 1931, a group of white teenagers started a fight with several Black teens and boys on a train. After getting off the train, the white teens told the sheriff they had been attacked. Two white women also claimed they had been raped. Nine Black teens in total were arrested for the rape. Some of the defendants were as young as twelve years old. This group of defendants became known as the “Scottsboro Boys,” for the town in Alabama where the first trial was held. The initial trials happened quickly, with as little as a day for each trial. The lawyer defending the teens hadn’t practiced law in many years, and was assisted by a real-estate lawyer from Tennessee who was unfamiliar with both the case and Alabama state law. The defense offered no closing arguments, and did not address the prosecution’s request the defendants be sentenced to death by the electric chair for the crime. The all-white jury deliberated the first case, involving two of the defendants, for less than two hours before finding the defendants guilty.

After the initial trials found all but one of the defendants guilty, the case was appealed several times. The appeals claimed that the all-white jury was biased, the defense lawyers were ineffective, and the sentences were unfair. When the new trials were held, one accuser admitted that she had invented the allegations of rape. In 1932, the case reached the Alabama Supreme Court, which affirmed seven out of the eight death sentences. After several more appeals the case went before the US Supreme Court, where charges against four of the defendants were dropped. The rest of the defendants either eventually escaped or were released from jail. The one defendant who had received the death sentence in the final trial violated his parole and went into hiding, and later wrote a book about his experiences after being pardoned by the governor. In 2013, the remaining three defendants whose convictions hadn’t been overturned and who hadn’t yet been pardoned received posthumous pardons. The case has become a leading example of the injustice of all-white juries, and has been adapted in many books, plays, and movies. Scottsboro is now home to the Scottsboro Boys Museum and Cultural Center.

There are many parallels between the Scottsboro cases and To Kill a Mockingbird. As in Scottsboro, Mockingbird concerns the allegations of the rape of a white woman by a Black man, a crime punishable by death penalty in Alabama at the time. Also as in Scottsboro, one major problem in Tom Robinson’s trial is that the jury is racially biased. They therefore find him guilty even though Atticus Finch makes it obvious that Tom was physically incapable of committing the crime. This is similar to how the jury in one of the later Scottsboro trials disregarded the accuser’s admission that she had invented her testimony. In addition, as in Scottsboro, To Kill a Mockingbird features a lynch mob that seeks to kill Tom before he can face a fair trial. While the defendants in the Scottsboro case were being held in jail a lynch mob demanded the teens be turned over to them; the sheriff called the Alabama National Guard to protect the jail and moved the teens to a new location. Throughout the twentieth century, Black men were frequently lynched on the basis of someone’s unfounded accusation, sometimes for violations as small as allegedly winking at or catcalling a white woman. The lynchers usually went unpunished for the murders.