Sydney woman admits killing her lover's baby

A woman who killed her lover's baby convinced him of her innocence for two years after the act, a Sydney judge has been told.

Even after admitting the crime to police, the woman tried to implicate a stranger she met by chance in prison, according to a statement of agreed facts tendered in the NSW Supreme Court yesterday.

The 23-year-old woman, who cannot be named for legal reasons, has pleaded guilty to the manslaughter of the 16-week-old baby girl at Dubbo, in central western NSW, in July 2004.

She also has admitted attempting to pervert the course of justice.

During a sentencing hearing, the woman told Acting Justice Jane Mathews: "I am sorry, I think about it every day".

According to the facts, two weeks before the baby died from a blunt force head injury, the woman had tried to enrol in a heroin addiction treatment program her partner had just started.

In three police interviews the woman denied harming the child but finally, in July 2006, she made various admissions.

She said she had been extremely tired and "very stressed out and hanging out from the drugs".

She said the baby would not settle and when she put the infant to bed, "I must have put her down way too hard, and that's when she hit her head, like, on the wooden part".

The woman admitted lying to police, her partner, and others, saying she had feared losing her boyfriend and receiving a long jail term.

"Covertly obtained evidence during the course of the two-year homicide investigation showed that (the father) had a genuine belief that the offender had not harmed or killed his baby daughter," the facts said.

After being refused bail in July 2006, she was placed in a cell for about two hours with a stranger, whom she asked to admit to killing the baby.

The woman wrote to her lover, saying the stranger was "maddley (sic) in love with you bub, she told me why she dun (sic) it because she set me up to make you hate me".

Worried about being implicated, the second woman handed authorities a letter the killer had slipped into her cell, detailing how she should say she had committed the crime.

The baby's father told police of a September 2006 letter in which his de facto partner instructed him about making a false statement.

He told police the letter "made me sick the first time", saying the woman had always maintained she had never hurt his daughter.

The sentencing hearing will continue on October 19.

- AAP