The trial of the man accused of murdering British backpacker Grace Millane begins today in the High Court at Auckland.

Photo: RNZ / Claire Eastham-Farrelly

Ms Millane was staying at a hostel in central Auckland when she went missing on the eve of her 22nd birthday in December last year.

A 27-year-old man was charged with murder a day before her body was found in a bush on Scenic Drive in the Waitākere Ranges.

The man, who has name suppression, pleaded not guilty to the charge in the High Court at Auckland in January.

He is accused of murdering Ms Millane between December 1 and 2, 2018.

The trial, before Justice Moore and a jury, is set down for five weeks.

Ms Millane's family have flown from Essex in the United Kingdom and are expected to be at court for the trial.

The missing person search

Ms Millane was reported missing on 5 December, 2018.

She had left the UK six weeks earlier to travel the world after finishing university.

She had been to South America before heading to New Zealand in late November.

Ms Millane had already visited the Bay of Islands and had onward travel booked from Auckland.

She was last seen on CCTV footage on 1 December, 2018, police said at the time.

Her family became worried after they hadn't heard from her for several days, her brother Michael Millane said.

"We sort of noticed Gracie hadn't really texted back or hadn't read anything, which was obviously really strange because it was her birthday," he said.

"We thought maybe it's just the time zone, sort of catching up, but we looked into it and realised her messages hadn't been read or delivered."

Missing person posters were put up around central Auckland and her father, David Millane, flew to New Zealand to help with the search.

Photo: RNZ / Claire Eastham-Farrelly

"Grace is a lovely, outgoing, fun loving, family orientated daughter. She's usually in daily contact with family on social media," he said at a press conference with police.

Mr Millane was in Auckland when investigators found her body, and later attended a vigil in the city to remember his daughter.

Other vigils were held around the country.

Ms Millane's body was repatriated to the UK for a funeral, attended by lead investigator Detective Inspector Scott Beard, near her home in Essex.

The court trial

The Crown's case will be prosecuted by Robin McCoubrey, Brian Dickey and Litia Tuiburelevu of Meredith Connell.

The accused is represented by Auckland defence lawyers Ian Brookie, Ron Mansfield and Claire Farquhar.

Anybody accused of a crime in New Zealand is presumed innocent until proven guilty in a court of law.

It is up to the prosecution to prove guilt; a defendant does not have to prove their innocence.

The prosecution must prove a disputed charge or allegation to a high standard, that is beyond a reasonable doubt.

Jurors can never know with 100 percent certainty but must be sure that a defendant has committed a crime to deliver a guilty verdict.

The trial before Justice Moore and a jury of 12 is set down for five weeks.

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