Man to serve 18 years for 'horrific' murder of Christchurch prostitute

A man who repeatedly ran over a prostitute in his car, before throwing her body in a river, will serve at least 18 years of an indefinite jail term after a judge described his crimes as "absolutely horrific".

Justice Lester Chisholm today imposed preventive detention and a life sentence with a minimum non-parole period of 18 years on Peter Steven Waihape for the brutal killing and rape of the 24-year-old Christchurch prostitute in December last year.

Waihape, 29, was also sentenced to a total of 10 years in jail for the abduction and sexual violation of a teenager just three days earlier, but this jail time will be served alongside the greater sentences.

In the High Court in Christchurch, Justice Chisholm told Waihape the killing of the prostitute "couldn't get much worse".

He had repeatedly run her over and rammed her through a concrete wall despite her cries for mercy, and even got out of his car to kick her while she lay injured.

Witnesses reported hearing him laugh as he ran her over. His victim's hands were bound when he threw her body in Christchurch's Avon River.

"The ultimate indignity was that you used her as a stepping platform to get out of the river."

Waihape's lawyer, Leuatea Iosefa, said Waihape had sought psychiatric help at least five times during the period of the two attacks, and spoke of what he had done in the first attack and what he might do.

Mr Iosefa was "frankly appalled" the mental health providers Waihape approached appeared to treat the claims seriously.

But Justice Chisholm said: "The information I have read does not lead me to the conclusion that any professional should bear responsibility for the shocking events that were to follow".