RICHMOND, Va. — A jury on Thursday acquitted a Virginia man of killing his stepson, who investigators said was sexually assaulted before being smothered with a pillow in a 2015 incident.

Marcaday Duncan-Houston, 37, was acquitted of aggravated malicious wounding and other charges after he told the jury that his stepson, 12-year-old Trae Johnson-Houston, knew what he was doing the night of Feb. 6, 2015, Richmond's The Richmond Times-Dispatch reported.

Prosecutors said Trae admitted to talking back to Duncan-Houston, then a Richmond fire captain, as the two argued.

According to police, Trae's mother dropped him off at his stepfather's home for a sleepover that night. During one argument, Trae apparently asked Duncan-Houston why he talked back to him, and Duncan-Houston replied that Trae knew what he was doing, prosecutors said. Trae remained awake and reached up to kiss his stepfather on the lips, triggering another argument, they said.

On the following night, Trae told his mother that he couldn't open his mouth because it was cold. Duncan-Houston, who said he'd touched Trae on the neck during one of their arguments, pushed Trae away with both hands, saying "That's it, you're never seeing your friends again," according to prosecution.

Trae started to cry, so Duncan-Houston kissed the boy on the cheek, he testified. Trae said he didn't hear any more fighting, and at that point, Duncan-Houston took him into a bedroom and suffocated him with a pillow, he testified. Trae's mother discovered him dead in the bedroom the next morning.

Defense attorneys said the boy made the entire story up, based on memories he described to his parents only weeks before his death. They alleged that Trae had been raped and sodomized in the days before his death.

Trae's mother testified she was far too upset by the sex allegations against Duncan-Houston and by the murder accusations to call authorities immediately. She said she wanted her son buried in a close-fitting white shroud so that he wouldn't be known for having been raped before he died.