"Probably my tattoos, and being Maori and my background and previous things I had been in prison for," he told Radio Live this week.
On Monday, a High Court judge took just a few minutes to dismiss one charge of murder against King, when prosecution lawyers admitted there was not enough evidence to go ahead with the trial.
Defence lawyer Peter Williams QC, who delayed retirement to take the case, was convinced of his client's innocence after just a few moments in his company.
"Police spent an enormous amount of time searching for evidence that would convict Mr King. They tried very deceptive methods to gain incriminating evidence against him but the fact is, they got the wrong man."
King's nightmare began on January 21, 2008, when his neighbour's naked body was found in a pool of blood on the floor of her Onekawa flat.
Maihi-Carroll, a 46-year-old grandmother, had been stabbed many times and may have been sexually assaulted.
King had just been released on parole after being convicted of the aggravated robbery of a Napier TAB but he was "trying to put his life back together", says Mike Crawford, a private investigator who spent a year on the case.
Crawford says police discovered Maihi-Carroll, who had separated from her husband, was having an affair with another neighbour.
A speck of his blood was found in the dead woman's house - and police apparently accepted his explanation he had cut himself shaving. The DNA of a second, unidentified man was found on a glass and an ashtray, says Crawford.
Witnesses spotted a blood-smeared cyclist near Maihi-Carroll's house on the morning she died. But despite those loose ends, detectives were convinced King was their man.
His phone was tapped, his car bugged, and his every move monitored by electronic surveillance.
Six weeks after the murder, police interviewed King's colleagues at the Hatuma Foods pea-processing plant in what was later referred to in court as the "Hatuma" evidence.
They claimed King had talked about the murder the day before police released any details - proving his guilt.
But after discovering dry cleaners were late delivering the workers' uniforms, investigators were able to prove police had the wrong day.
Crawford added: "These were people working 12-hour shifts, seven days a week, and yet three or four of them could remember the exact details of a brief conversation held months earlier.
"They were people who, when they weren't working, were drinking grog or smoking cannabis. You have got to question their credibility, but the police obviously didn't."
King's first murder trial was aborted last June after two days with no evidence heard.
And while Napier police have ruled out a retrial, they stand by their investigation.
Inspector Sam Aberahama said: "My team did the best job they could of investigating this crime. I believe we put the right man before the court to face the murder charge."
For Maihi-Carroll's family, last week's decision was a devastating blow.
Brother Whiu Carroll said: "We are taking stock as a family. This has been very difficult."
And Onekawa locals are coming to grips with the fact there could still be a murderer in their midst.
Lyn Pune, who lives next door to Maihi-Carroll's former home, said: "Now that he's [Zion] been cleared, that means there's a murderer out there. I'll be locking up the windows."