Part one of two. Read part two here.

On a summer day in 1980, 19-year-old Andre Davis stepped off a train 125 miles south of his native Chicago. He expected his visit would last the summer. Little did he know he wouldn’t return home for more than 30 years.

Some time spent in Rantoul, his family thought, would be good for him.

Friday, August 8, 1980, was steaming. Andre headed over to the Tuckers’ at around 10 AM to waste the day away with Maurice while Sonny was in and out of the house. They took out weights from the utility room, where Maurice slept, and lifted barbells in the backyard under the blazing sun. They played records. Most ambitiously, they climbed the generous fruit trees that leaned from a neighbor’s house into the yard and picked apples and pears. But mostly they sat on the stoop drinking beer and cheap Wild Irish Rose wine and listening to breaks.

At around 6:30 PM, Rand began knocking on doors. He went to the Tuckers’ house and heard a stereo playing on low volume. He knocked but got no answer, figuring that somebody had left the stereo on. He then got in his car to continue the hunt. The Spraggs didn’t own a phone, so Becky flagged down a passing police car and told the officer that Brianna was missing. Officer Ronald McLemore began checking around the neighborhood.

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Shortly before 8 PM, as the officer was conducting his search, “a black man come up there in a car—I don’t remember the car—and he knocked on the [Tuckers’] door,” Becky later recalled. It was Don Douroux. He was carrying a glass of Kool-Aid and wearing a T-shirt with the words master blaster emblazoned on the front and don juan on the back. A short while later, Rand and Becky saw Don walk out the back door of the house and lock it up. Becky walked up and asked if they could look for Brianna inside. Perhaps she had wandered over? At first Don demurred—it wasn’t his house, he said. But he relented and they searched the house while he supervised. No sign of Brianna. Rand did notice a wet red stain on the twin bed in the messy utility room where Maurice slept. He passed his finger across the stain, but chalked it up to “a single man living there and having girlfriends, you know,” he later said. The room had clothes strewn everywhere. Don saw the Spraggs to the front door, and went to lock up the back.

Andre later would deny Don’s account. He said he never claimed to have been with a woman that day, let alone killed anyone. His recollection was that he left the Tuckers’ between 6:15 and 7 PM, when Maurice and Sonny were still at the house—a point on which all parties agreed—and headed over to Don’s. Finding nobody there, he said he went to a friend’s house across the street and made a phone call. He said he then returned to Don’s and waited for him until he came home, which was about 20 minutes later. According to Andre, the two drank some Kool-Aid together and discussed getting high later on, after which Don told him he was going for a run. (Don went over to the Tuckers’ instead.) Andre recalled Don returning 20 minutes later, and the police arriving soon after.

Next on the stand was Robert Beams, an FBI special agent who headed up the Washington lab where the evidence in the case was tested. At the time, the FBI was the only agency in the country capable of doing sophisticated forensic analysis. Type O-positive blood, the most common blood type in the United States, covering about 45 percent of the population, was found at the scene. Brianna was type O-positive, as is Andre. Moreover, Andre is what’s called a “nonsecretor.” Eighty percent of Americans are secretors, individuals whose blood type is present in the rest of their fluids. Andre is among the remaining one-fifth of the population who do not have blood-group substances in their saliva, urine, sweat, and semen. Beams told the court that a mattress and bedsheet with semen on them had been sent to him for testing. Both contained no trace of blood-group substances—meaning they came from a nonsecretor, like Andre.