Fifty years ago this month, an unknown young writer from Alabama published her first novel. Harper Lee’s Pulitzer Prize-winning masterpiece, To Kill a Mockingbird, still sells almost a million copies a year. Charles J. Shields, author of Mockingbird: A Portrait of Harper Lee, the only biography of the writer, talks about her in this interview with the Christian Science Monitor.

To Kill a Mockingbird seems to be closely drawn from actual events in Harper Lee’s life. But is it an oversimplification to say that Atticus was her father?

No, it’s an accurate statement. Her father was a great man in a small town. He was much respected, a partner in one of the largest law firms in the county, a director of the bank, a deacon at the local church, and twice elected to the state legislature, just like Atticus. Although he was more reserved than Atticus. No one could ever recall not seeing him in a three-piece suit, even when he golfed. And I have to say that he was a segregationist. People like him, whose parents had fought in the Civil War, as his had, genuinely believed that people were happier with “their own kind.”

But there were transformative events in his life.

Oh, yes. By the time he was an elderly man, when “To Kill a Mockingbird” came out, he was involved in an effort to redistrict the state to see that blacks were better represented in Alabama.

What about the trial he was involved with as a young attorney?

Lee had been practicing law for only a few years. He was appointed by a judge to defend two black men who were accused of murdering a white man. Now, Lee had never had a criminal case before. This method of doing business in the courts was informally called “Negro Law,” which means that you get a young, inexperienced white attorney to practise on some hapless black client. Some of those trials took as little as half an hour. [Note: The two men Lee defended were convicted and hanged. Lee never tried another criminal case.)

[Harper Lee] got her literal facts, however, from a case that happened right in Monroeville when she was a girl in the early 1930s. A black man was accused of raping a white woman. His trial lasted about six hours [longer than expected] because he had a pretty good alibi. He was at work at the brick factory and he didn’t know the woman. [The convicted man] lost his mind in prison and was remanded to a local insane asylum.

Truman Capote was Harper Lee’s next-door ­neighbour and closest childhood friend. Did he ever acknowledge himself as Dill in her novel?

Oh, yes. He wrote to Detective Dewey with whom he became friends in Kansas while working on “In Cold Blood” and said that Harper Lee, or Nelle [the name used by Harper’s family and friends], “has a book coming out and you must get it. It has a character named Dill in it and that’s me.”

Why did the longtime friendship between Lee and Capote eventually sour?

It was jealousy on Truman’s side, disappointment on Nelle’s side. Here was this next-door neighbour of his who never craved fortune or the spotlight and she wins the Pulitzer Prize. So it was jealousy on his side and disappointment on Nelle’s because Truman drifted into a sea of drugs and alcohol and became an undependable friend.

Why didn’t she succeed at producing another book?

I think that you write best when you are passionate about something, and that book was sort of a gift to her father. Her father was disappointed that she had dropped out of law school and gone to New York to be a bohemian. She wanted that book to work and she wanted her father to be a hero. And she achieved that. [Also] her support group fell away.