Life term urged for lying NSW child killer

A Christian hip hop producer convicted of the murder of a seven-year-old whose fatal injuries he tried to blame on a fall from a pogo stick should be jailed for life, a court has heard.

Kodi Maybir's "horrific, horrendous, inhuman" treatment of the boy, who died at Maybir's Oatley music studio in Sydney's south in May 2013, was in the worst category of offences, crown prosecutor Chris Maxwell told the NSW Supreme Court on Friday.

Justice Robert Allan Hulme said it was still unclear exactly how the boy had died, as Maybir had repeatedly lied to the court and had given four different versions of what caused the boy's fatal injuries.

"They have been pretty poor attempts on each occasion," Justice Hulme told the court.

During the trial, numerous videos of the boy that were taken in the lead up to his death were played to the court.

In one, Maybir encourages the boy's siblings to punch the boy, who cannot be named, while in others the boy's mother, Kayla James, calls him a "little s***".

James is serving at least 10-and-a-half years for the boy's manslaughter.

Maybir also made the boy eat his own faeces, wear a dirty nappy on his head and undertake gruelling exercise regimes.

In one punishment he made the boy stand barefoot on a coffee tin with outstretched arms.

Maybir claimed he was just "fooling around" when he grabbed the boy and threw him in a wrestling move and said at trial this was how the seven-year-old's fatal injuries were incurred.

"It is a highly unusual, one must say, cruel act," Mr Maxwell said.

He said Maybir had committed the murder in circumstances of aggravation and asked Justice Hulme to sentence Maybir to jail "for the term of his natural life".

Maybir will be sentenced at a later date.