A man who bashed a mother of three to death at Wellington's Basin Reserve cricket ground 15 years ago still does not understand what triggered the violent killing, the Parole Board says.
David William Taylor, 56, was last week declined parole after he appeared before the board late in April.
Taylor was sentenced to life in prison for the brutal killing of 41-year-old Marie Copley on June 20, 1997.
Taylor met Ms Copley in a Wellington city bar on the night of June 19.
But early on June 20, as they walked through the Basin Reserve, Taylor kicked, punched and bludgeoned her to death.
Her body was so badly beaten that a birth mark on her leg had to be used to identify her.
Taylor had a history of sex offending, and last year he waived his right to attend a parole hearing so he could attend the Kia Marama Child Sex Offender Treatment Programme, which he finished in January this year.
Parole Board chairman Judge Sir David Carruthers said last week the sentence which was of principle concern for the board was now not his sex offending, but the very violent murder.
"There seems to be no concentration on that in the reports before us.
"He has no real insight or understanding into why he committed that murder and whether it connects with other sexual offences that he has committed in the past.''
Taylor had no idea what the triggers were, although he was working on it, Judge Carruthers said.
Taylor had developed a plan for himself which involved a release to work over a long period, but this seemed to be too soon, the Parole Board found.
"He first has to move past the intervention phase of his sentence and show that he has made considerable gains in that area before he can look at the process of reintegration which clearly awaits him.''
Judge Carruthers said the question of postponement would be considered the next time the board met Taylor.