The world’s longest serving prisoner has been exonerated in Japan

An 88-year-old man who is the world’s longest serving prisoner has been overturned by a Japanese court, after it was found that the evidence used against him was false.

Iwao Hakamada, who has been on death row for more than half a century, was found guilty in 1968 of killing his boss, the man’s wife and their two young children.

He was recently retried due to allegations that investigators may have planted evidence that led to his conviction for murdering four people.

More than half a century spent on death row took a toll on Hakamada’s mental health, however, meaning he was ineligible to attend the trial where his exoneration was finally granted.

Hakamada’s case is one of Japan’s longest and most famous legal sagas, and has drawn widespread public interest, with about 500 people lining up for seats at the Shizuoka court on Thursday.

When the verdict was handed down, Hakamada’s supporters outside the court cheered “banzai” – a Japanese exclamation that means “hurray”.

Hakamada was not in court, as he had been excused from all proceedings due to his mental breakdown.

He has been under his sister’s custody since 2014, when he was released from prison and given a chance for a retrial.

A former professional boxer, Hakamada was working at a miso processing plant in 1966 when the bodies of his employer, the man’s wife and two children were found in a fire at their home in Shizuoka, west of Tokyo. All four were stabbed to death.

Authorities accused Hakamada of killing the family, burning down their house and stealing 200,000 yen.

Hakamada initially denied robbing and killing the victims, but later gave what he described as a forced confession following beatings and interrogations that lasted 12 hours a day.

In 1968 he was convicted of murder and arson, and sentenced to death.

A decades-long legal saga finally unraveled the clothes found in the miso tank a year after Hakamada’s arrest. Those clothes that are said to be stained with blood, were used to incriminate him.

However, for many years Hakamada’s lawyers argued that the DNA found on the clothes did not match hers, making it possible that the items belonged to someone else. The lawyers also suggested that the police could have fabricated evidence.

Their argument was enough to convince Judge Hiroaki Murayama, who said in 2014 that “the clothes did not belong to the defendant”.

“It is unfair to continue detaining the accused, since it is clear that he is innocent,” Murayama said at the time.

Hakamada was subsequently released from prison and granted a retrial.

The protracted trial meant it took until last year for the trial to begin – and it was not until Thursday morning that the court handed down its verdict.

While the genetic argument was dismissed, the judge found another argument of the defense lawyers to be credible – that the red stains found on the clothes could not be blood, as blood would not remain red on the clothes after being soaked in miso for a year.

The judge found Hakamada innocent and concluded that key evidence presented by the prosecution was false.

Decades of imprisonment, mostly in solitary confinement due to constant death threats, took a toll on Hakamada’s mental health, according to his lawyers and family.

His 91-year-old sister Hideko has long advocated for his release. Last year, when the trial began, he expressed his relief and said “at last the weight has been lifted from my shoulders”.

Retrials of death row prisoners are rare in Japan – Hakamada’s is only the fifth in Japan’s post-war history.

Along with the United States, Japan is the only G7 country that still imposes the death penalty, where inmates on death row are notified of their execution hours in advance.