A man convicted of murdering a Christchurch woman has admitted a sexual crime against another woman the same day that Vanessa Pickering went missing.
In November last year, Malcolm Chaston admitted that he killed Ms Pickering, 27, but the court said his guilty plea could not be reported as it would prejudice his right to a fair trial on another matter.
Chaston, a freezing worker in his 40s, was also accused of assaulting another woman, who has name suppression, with intent to commit sexual violation - a charge he denied.
That trial was due to begin on Monday, but Chaston changed his plea to guilty at the last minute, meaning the judge could lift the suppression on his previous convictions.
The court heard Chaston assaulted the woman on 8 February last year, the same day that Vanessa Pickering went missing from the suburb of New Brighton.
Ms Pickering's body was found in the Port Hills, near Christchurch, three days later.
Chaston will be sentenced on 18 April. The Crown is seeking a sentence of preventative detention.