DALLAS -- A Dallas-area man was sentenced to death Saturday for killing his children's baby sitter to prevent her from testifying that he raped her.

Franklin Davis admitted in court to killing 16-year-old Shania Gray, describing how he lured her into his car outside her school, shot her and dumped her body in a river. But he said he killed her out of revenge and hatred, not to obstruct the sexual assault case that was nearing trial.

Mug shot of Franklin Davis, courtesy of Carrollton Police Department.

A Dallas jury convicted Davis of capital murder Tuesday before sentencing him to death.

Gray was remembered as a vivacious, friendly girl who often played basketball in the family driveway. Most people did not know that she was at the center of the sexual assault case against Davis.

Her mother told police in the Dallas suburb of Mesquite that Davis sexually assaulted Gray while she was baby-sitting his children. Davis, known by the nickname "Wish," exposed himself and had sex with the girl four separate times in 2011, according to a police affidavit.

Davis continued to deny the allegations at his trial.

"She lied," Davis said on the stand, according to Dallas television station KTVT. "She ruined my life. She took everything from me, everything I work so hard to get. She took it."

In the days before he killed Gray, Davis called and sent her text messages pretending to be a boy and asking her questions about the sexual assault case. The day of the killing, Gray got a text message saying her new friend was outside her school to surprise her.

Davis' defense attorneys argued he was trying to do his own investigation after police did not. But prosecutors scoffed at that notion.

"You know it, I know it and he knows it," prosecutor Russell Wilson told jurors, according to The Dallas Morning News.