The long-awaited double-murder trial for a mum accused of killing both of her primary school-aged children - leaving their bodies in an Auckland storage facility before moving overseas - began today with an awkward silence.

“Guilty or not guilty?” Justice Geoffrey Venning asked again when Hakyung Lee, 45, declined to respond as the charges were put to her.

“I’ll record a not guilty plea,” the judge added when she remained mute.

Venning later noted to jurors that they will likely be tasked with determining if Lee was insane at the time of her children’s deaths. It’s the first time a possible not guilty by reason of insanity defence has been mentioned in open court for the high-profile case.

The former Papatoetoe resident was charged and extradited from South Korea almost three years ago.

The High Court at Auckland trial is expected to last four weeks.

“She is charged with the murder of her two children,” Justice Venning explained to the wider jury pool before the group was narrowed down to a six man, six woman panel. “At the time of their deaths, they were 8 and 6 years old.”

Hakyung Lee appears in Manukau District Court on November 30, 2022, hours after her extradition from South Korea. Photo / Dean Purcell

Police descended upon a South Auckland residence in August 2022 after a family that had purchased items from an abandoned storage unit at auction made an unsettling discovery upon opening two suitcases.

Inside were the remains of Yuna Jo and her little brother, Minu Jo.

Months later, Lee was charged with having killed both children in Manukau sometime between June 23 and June 27, 2018, meaning they would have been dead for more than four years at the time of the discovery.

She was taken into custody in South Korea at the request of New Zealand law enforcement and arrived in Auckland in November 2022.

The defendant was born in Korea but later obtained New Zealand citizenship. Immigration records suggest she returned to Korea in 2018.

Lee’s trial was initially scheduled for April 2024 before a different High Court judge, but it was pushed back by almost a year and a half at the last minute due to fair trial issues. The media is not currently permitted to elaborate on the decision.

Lee’s case has attracted widespread media interest in New Zealand and abroad.

Crown solicitor Natalie Walker indicated to jurors today that she and fellow prosecutors, Jay Tausi and Jong Kim, would be calling to the witness box a toxicologist, a school teacher, storage facility staff and members of the children’s extended family.

Lee is technically self-represented but it is unlikely she will take an active role in the trial. She has requested to observe the trial remotely from another courtroom, the judge indicated today.

Defence lawyers Lorraine Smith and Chris Wilkinson Smith are serving as her standby counsel.

Lee kept her head deeply bowed - as has been the case at all previous hearings - while she sat in the courtroom dock today between a security officer and her interpreter.

Craig Kapitan is an Auckland-based journalist covering courts and justice. He joined the Herald in 2021 and has reported on courts since 2002 in three newsrooms in the US and New Zealand.