Lawyers for an alleged murderer that China wants extradited have told the Supreme Court the decade-long case has gone too long, that "enough is enough" and the case must be thrown out.
The order to handover Kyung Yup Kim is New Zealand's first extradition case involving China.
The Korean-born New Zealand resident is accused by Chinese police of murdering a woman in Shanghai in 2009, which he denies.
Kim's extradition was twice-approved by the former Justice Minister Amy Adams after getting diplomatic assurances he would be treated fairly and not receive the death penalty.
But last year, the Court of Appeal blocked the extradition, ruling the Government needed to consider human rights risks and telling the now-Justice Minister Andrew Little to question the assurances given.
The Crown appealed the ruling, arguing the minister sought high level assurances such as the ability to closely monitor the case.
But lawyers for Kim told the Supreme Court on Wednesday that an injunction to stop the extradition was the only answer, citing risk of torture and unfair trial practices.
"The problem posed by extradition to China is intractable," said Ben Keith.
He said he could find few instances where Western countries had extradited people to China in the past decade, except a "clump of Spanish cases." Spain has an extradition treaty with China.
One of the assurances secured through diplomatic channels was that a New Zealand consular official could monitor Kim's trial.
But Mr Keith said he would have more confidence in an NGO.
"Extradition is about surrender for fair trial, it's not about surrender at any cost," said Mr Keith.
China first ordered Kim's extradition in 2011. Since then the case has been in and out of the courts in New Zealand and Kim served five years on remand in prison.
His lead counsel, Tony Ellis, said he'd "suffered enough."
"It's been too long and it's not safe to send him back there," said Mr Ellis.
But the Crown opposed such relief and said it would amount to the court taking the matter into its own hands.
The Solicitor General told the court the Justice Minister was the "proper place" for the case to be decided.
The Supreme Court has reserved its decision.