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Helen Roberts says she "could not imagine the person I met to have been so horrifically violent"

Two decades ago, Helen Roberts met Tennessee death row inmate Christa Pike to understand the woman behind the brutal murder of Colleen Slemmer.

Aged 30, Pike had served 11 years on death row and was the youngest woman to receive the penalty in the United States when Roberts interviewed her as real life editor of women's lifestyle magazine.

Pike, now aged 50, faced her long-awaited execution on Wednesday, but survived two lethal doses of pentobarbital and remains in critical condition.

Roberts, who has been following the developments, reflected on her conflicting encounter with Pike and how it had stayed with her as both a journalist and a human being.

"It was really hard sometimes to reconcile the woman in front of me to the crime she had committed," she said.

"They were like two very separate people, I could not imagine the person I met to have been so horrifically violent."

Image source, Helen RobertsImage caption, Journalist Helen Roberts interviewed Tennessee death row inmate Christa Pike 20 years ago

Roberts entered Tennessee's maximum-security prison for women, now known as Debra K Johnson Rehabilitation Center, in Nashville in December 2006.

"I'd never been into a prison, let alone a maximum security prison, so I was quite nervous and a bit unsure of how it was going to go, a little bit intimidated I suppose," she recalled.

Roberts, from Conwy in north Wales, was working for More Magazine and flew to the US for the interview.

After passing through security checks and several doors, she met Pike through a glass window, and carried out the interview using a speaker.

They were just years apart in age and Roberts said she tried to go into it without any kind of judgement, but admitted she expected a "very honest, brutal woman".

But the person she met was much different.