- In this Sept. 29, 1955 file photo, Willie Reed, right, a witness in the Emmett Till murder case in Mississippi, stands outside the door of his apartment in Chicago under guard by Detective Sherman Smith. Reed, who changed his name to Willie Louis and told no one of his connection to the case, not even his future wife, was brought to Chicago by friends after his testimony in the trial. His wife, Juliet Louis said Wednesday, July 24, 2013, that her husband died July 18, 2013 at a hospital in Oak Lawn, Ill. He was 76. (AP Photo/Charles Knoblock, File)

CHICAGO (AP) β€” Hearing the screams of 14-year-old lynching victim Emmett Till from inside a Mississippi barn left a teenage farm worker with an unbearable choice. He could tell a courtroom and risk paying for it with his life or keep quiet and let those screams eat away at his conscience.

Grisly photos of Till’s mutilated body, discovered three days later in a local river, left Willie Louis with no doubt: He, a black man in the racially divided America of the 1950s, would testify against two white men accused in the black teen’s slaying.

Louis died July 18 at age 76 at a hospital in a suburb of Chicago, the city he fled to in fear of his life after the 1955 trial, his wife, Juliet Louis, said in an interview Wednesday.

Louis, a central figure in one of the most pivotal moments in America’s troubled history with race, had drifted into obscurity. For years, he told his story to no one, not even his future wife, who had followed the trial closely as a child.

Till’s torture and killing galvanized the civil rights movement. The Chicago boy was visiting an uncle and had been warned by family to be on his best behavior in the segregated South. On Aug. 28, 1955, two white men abducted him from his uncle’s home because he had whistled at one of their wives. They admitted to the kidnapping, but claimed they just wanted to scare the boy and that they eventually turned him loose.

When his body was pulled from the river, his left eye and an ear were missing, as were most of his teeth; his nose was crushed, and there was a hole in his right temple. His body had been weighted down with a cotton gin fan tied around his neck with barbed wire.

The only witnesses prosecutors had were the boy’s uncle and a cousin, and all they could say was that they had seen Till taken away. Then, news reporters helped track down Willie Louis, who had heard the beating taking place for hours.

“In the pictures, I saw his body, what it was like. Then I knew that I couldn’t say no,” Louis recalled in a “60 Minutes” interview in 2004 about the testimony he gave. He said Emmett’s screams haunted him.

“I heard this screaming, beating, screaming and beating,” he said.

Despite his speaking out, an all-white jury took barely an hour to acquit the two men, Roy Bryant and his half-brother J.W. Milam.

A few months later, after assurances they couldn’t be tried again, the two men confessed to the killing in a magazine article for which they were paid a few thousand dollars for the “true” story.

For his own safety, Louis had to be smuggled out of his native Mississippi and taken to Chicago. Then known as Willie Reed, he changed his last name and was put under police protection.

Louis met his future wife in the early 1970s at a hospital they worked at in Chicago, when Louis cheekily asked the nurse’s aide for a kiss as they were lifting a patient together onto a gurney.

“So I went over to the other side and kissed him on the jaw. And that’s how we started seeing one another,” she said with a laugh.

They married in 1976, and she discovered the connection with the Till case eight years later, when one of Louis’ aunts mentioned it.

“I never really put that together that he was actually the young man that testified at the trial,” Juliet Louis said of her husband. “We thought he was crazy. I know my mom said they going to kill him too.”

She understood that talking about it was painful for him.

“He used to have real nightmares and things,” she said. “All his life it bothered him. When he would talk about it, sometimes tears would be in his eyes.”

Till’s relatives, historians and documentary makers, meanwhile, had been searching for Willie Reed, wondering what had become of him. A New York filmmaker eventually tracked him to his home and later introduced him to Till’s mother, Mamie Till Mobley.

“She just cried when they took him over there,” Juliet Louis recalled. “They always kept in touch after that.” Till’s mother died in 2003.

Besides his wife, Louis is survived by a stepson, seven grandchildren and 21 great-grandchildren.

Copyright 2013 The Associated Press.