CHARLOTTE, N.C. — A federal judge sent Royce Mitchell back to prison for 30 months Wednesday, a day after hearing taped testimony that Mitchell twice had sex with his adopted teenage sister, who was fatally shot in September.

U.S. District Judge Bob Conrad said he found Tiffany Wright's taped interview “credible” and “reliable.” He found that Mitchell had committed statutory rape and taken indecent liberties with Tiffany – thus violating conditions of his release from prison in 2007.

Mitchell shook his head as Conrad announced his rulings.

Conrad heard the taped testimony Tuesday. Tiffany, who was pregnant when she was killed waiting for her school bus Sept. 14, told a detective about sexual encounters with Mitchell, 36. She also said she believed Mitchell was the father of her unborn child.

Tiffany said she wasn't forced or threatened.

Mitchell's attorney argued Tuesday that Tiffany made the whole story up.

But Judge Conrad found the preponderance of the evidence shows that sex likely occurred.

Now, Mitchell is going back to prison for violating terms of his 2007 release from prison on a drug trafficking charge.

The story of Tiffany's life and death rocked Charlotte, as details of how the system failed to protect her have emerged.

Police charged Mitchell with statutory rape - but prosecutors dropped the case after a DNA test showed that Mitchell was not the father of Tiffany's baby. Without Tiffany alive to help make her case, prosecutors said they couldn't prove a crime beyond a reasonable doubt.

But the burden of proof is lower in probation revocation hearings.

In the taped interview, Tiffany softly described how the first sexual encounter happened at the home where she lived with Mitchell and his wife. She said Mitchell texted her: "Come downstairs."

When she did, she said: "He was like 'You wanna (have sex)' ... I think I shrugged."

The interview was taped in August during the Charlotte-Mecklenburg police investigation into allegations made by Tiffany, who was taken from the Mitchell's home and placed in foster care.

Detective Teresa Johnson testified Tuesday: "I did believe her."

Tiffany, a 15-year-old Hawthorne High School student, was eight months pregnant when she was killed. Police call Mitchell a "person of interest" in the killing. Doctors were able to deliver Tiffany's baby girl, but the infant died after a week in intensive care.

Tiffany also told the detective on tape that Mitchell took her to an abortion clinic in Charlotte in July. "I already knew it was too late to get an abortion so I really didn't care," she said.

Tiffany's foster mother Susan Barber also took the stand. She said Tiffany told her that Mitchell tried to persuade the girl to get an abortion and even offered to pay her $5,000.

Read the full story at CharlotteObserver.com