Image source, Tennessee Department of CorrectionsImage caption, If the execution proceeds, Christa Pike would be the first woman to be executed in Tennessee in more than 200 years
The US Supreme Court has declined to stop the execution of Tennessee inmate Christa Pike on the eve of the date appointed for her death by lethal injection.
Pike, 50, has been awaiting execution since she was convicted and sentenced to death in 1996 for the murder of a teenage classmate.
Hoping for a last-minute reprieve, her attorneys filed a petition with the high court ahead of her scheduled execution on Wednesday morning.
But after the high court's decision to deny that request, Pike will be the first woman to be executed in Tennessee in more than 200 years. Only 18 women have been executed in the US since the 1970s, compared to 1,663 men.
On Monday, Tennessee Governor Bill Lee denied a request for clemency from Pike, saying he would not intervene in her planned execution.
Pike was 18 when she and her then-boyfriend beat, tortured and murdered Colleen Slemmer, a 19-year-old they met at a job training camp for troubled teens.
Image source, Family handoutImage caption, Colleen Slemmer
Slemmer's murder created a media frenzy in Knoxville, Tennessee in 1995, when the teen was found with a pentagram - a symbol of Satanic ritual - carved into her chest. Pike has denied carving the pentagram herself.
She had accused Slemmer of insulting her and trying to steal her boyfriend. Two other residents at the camp later testified that Pike had bragged about the murder before and after, and showed them a piece of Slemmer's skull.
Her attorneys have argued that "an 18-year-old brain is not an adult brain" and that Pike was too young at the time of the murder to be sentenced to death for it.
At the time of her incarceration, Pike was the youngest person on death row, according to the Tennessee Department of Corrections.
She is due to be executed at 11:00 EDT (15:00 GMT) on Wednesday at Riverbend Maximum Security Institution in Nashville.
Additional reporting from Sareen Habeshian.
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