A mentally ill woman who pushed a stranger unprovoked in front of a train on a New York City subway platform has been handed a 20 year sentence.

Melanie Liverpool-Turner, 33, pleaded guilty to the killing of 49-year-old Connie Watton on March 4. She was sentenced on Friday.

Robert Watton, Connie's husband, shared a charged statement during the sentencing hearing asserting that he was haunted by the thought of his wife's last moments before she was pushed in front of an oncoming 1 train in Times Square on November 7, 2016.

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Melanie Liverpool-Turner, 33, pleaded guilty to the killing of 49-year-old Connie Watton on March 4. She was sentenced on Friday.

On November 7, 2016, Liverpool-Turner pushed Watton in front of a 1 train at Time Square

'I am haunted when imagining what happened to Connie that day by this demented piece of garbage. This murderer. Connie didn't deserve what happened to her,' he said, according to the New York Daily News.

He added: 'Melanie means darkness. You are heartless and you have no soul.'

Watton described his wife - who immigrated to the Philippines when she was 16 - as always willing to help others.

She had been 'extremely generous and giving' and was even sending money home to put her family through college. Two of her nephews were forced to drop out of school as a result of their aunt's death.

'I am haunted when imagining what happened to Connie that day by this demented piece of garbage. This murderer,' said the victim's husband

He added: 'Melanie means darkness. You are heartless and you have no soul'

'This murdering psychopath will be eligible for parole at the age that Connie lived until,' Watton added. 'Why should you get a second chance? Connie doesn't get a second chance. She is a danger to the public, and I wish nothing but life behind bars for this psychopath.'

Aaron Wallenstein, the woman's attorney, described how his client was failed by the system as her struggles with multiple mental illnesses were well documented.

Liverpool-Turner is said to have suffered from bipolar disorder and schizophrenia. Just a month before the murder, the woman witnessed someone commit suicide by jumping in front of a train in Union Square

Wallenstein mentioned that Liverpool-Turner had an 'unblemished' criminal record but struggled with years of sexual abuse as a child in Trinidad. She is also said to have suffered from bipolar disorder and schizophrenia.

Just a month before the murder, the woman witnessed someone commit suicide by jumping in front of a train in Union Square. At the time, she provided a false confession to the NYPD and told them that 'I hear voices. I push people in front of trains.'

She was admitted to the psychiatric ward at the Bellevue Hospital, but was released shortly after.

Ninetten days later, and Liverpool-Turner would kill Watton. Robert Watton has also sued the woman and the city Health & Hospitals Corporation. He is also suing the New York Transit Authority.

Aaron Wallenstein, the woman's attorney, described how 'unblemished' criminal record but struggled with years of sexual abuse as a child in Trinidad

'There is no disputing the loss of life of Mrs. Connie Watton is nothing short of a tragedy,' Wallenstein said, adding that his client's 'serious mental problems' could allude to 'society' needing 'to take some responsibility as well.'

Judge Michael Obus imposed the maximum sentence and called the incident every New Yorker's worst nightmare.

'Thousands of people ride the subway every day,' Obus said.

'This is truly the quintessential urban nightmare — when a total stranger takes it upon them self to snuff out someone else's life.