Someone should write a book about it. A documentary will have to do in the meantime. It’s very good, very sensitive, not entirely but quite consistently very one-way street.

Polk gives viewers a front-row seat at the trial, which is to say it cosies up to the Crown benches. The easy way to tell the story as a true-crime TV programme is to go on a long rant that Polkinghorne killed his wife, that he should have been found guilty, that he got away with it somehow or other. Early on, the documentary takes the hard way, and allows Polkinghorne to tell his story in an exclusive and really quite astonishing interview.

But by the third episode, around about the time I started running low on crackers, salami, and patience, Polk leaves viewers with little doubt.

There is a lot of prosecution and not a lot of defence. There is a lot of sympathy for Pauline Hanna, who died at Easter 2021 in her Remuera home, and not a lot of sympathy for her widower, as in zero sympathy.

But it makes for good tabloid TV – the ominous soundtrack, the slow drone footage above the mean streets of Remuera – and also succeeds as very powerful character studies of the quite weird Polkinghorne and the possibly even weirder Madison Ashton, his sex worker of preference who became his girlfriend in classic Pretty Woman fashion.

Both are interviewed. Both are fascinating. With Polkinghorne, it’s not so much what he says as what he does with his mouth, the way he twists his lips when he finishes a sentence. With Madison, it’s what she says as much as the sight of her massively altered lips, which wriggle all over her face.

She steals the show. Or rather the show stands back and lets her steal it, in awe of her plastic surgery, her shoes (“Ten thousand dollars a row,” she says, opening a closet to reveal lots of shoes in lots of rows), and her zingers. A personal favourite was her description of her sex-work clients: “Lots of accountants. Lots! If you’re an accountant, you’re a client.”

She’s a total ham, so much fun. But it’s an entirely useless performance. She became convinced Polkinghorne killed Pauline (“He knocked her off”) and was set to appear as a star witness for the Crown. “I think it’s really important what I have to say to a jury,” she tells the documentary. She didn’t say anything; she skipped town rather than give evidence. And so she settles for holding up his drug use and his lies and his double-life as smoking guns in the documentary. That sort of stuff may have cooked Polkinghorne’s goose in court but I doubt it. “A loose cannon,” as Herald court reporter Craig Kapitan describes her in the documentary.

Craig is interviewed extensively throughout Polk. He provides a concise and masterful commentary on the trial; he’s also fair and balanced. Another journo comes across as a yapping nitwit and I make a dramatic late entrance, seen stepping towards Pauline’s best friend, Pheasant Riordan, to give her a comforting hug after the verdict. Pheasant is interviewed. She says, “I think he’s a liar and a murderer.” Pauline’s brother Bruce Hanna is interviewed. His face tells you what he thinks.

Crown prosecutor Alysha McClintock is interviewed. She comes across as a sore loser although she also sounds like she has a terrible cold.

No one from the New Zealand Police is interviewed, which is probably just as well for the New Zealand Police. The investigating detectives lacked the authority of Detective Inspector Scott Beard, who featured heavily in the recent documentary on Grace Millane.

It’s interesting to compare Polk: The trial of Philip Polkinghorne with The Lie: The murder of Grace Millane. Just as the two murder trials were completely different, so too are the documentaries.

The Lie was resolutely, darkly serious, and made spooky use of filming the now-abandoned police station where Millane’s killer Jesse Kempson was interviewed. Polk witlessly films slow-motion drops of coffee falling into a cup, and enters into a spirit of high camp during its interviews with Ashton, with her many shoes, her many Chihuahuas, her enormous lips, and her enormous mammarian “bolt-ons”. But the comedy of it all is entirely faithful to Madison and her antic wit, and faithful, too, to the Polkinghorne story, which was so tawdry and so bizarre that it played out as an entertainment.

In any case both documentaries take the side of the Crown.

The Lie made minimal attempt to present Kempson’s case. At least Polkinghorne has his say, and at length, with that trembling little mouth. The two programmes have something else in common: defence lawyer Ron Mansfield, who represented Kempson and Polkinghorne.

Mansfield is despised in The Lie and criticised in Polk. Neither documentary credits the sheer hard work and powers of concentration that he brought to his role as an advocate. His defence of Polkinghorne was his masterpiece but the impression of him in Polk is someone tricky and devious. You may think that just by his appearance: it’s strange that I never noticed until watching the show how much Mansfield and Polkinghorne look alike, with their shaved heads and white whiskers close to their red faces. They could be brothers.

On the subject of family, I may be imagining things but I think the show was making innuendos and loaded little suggestions that Polkinghorne was in some which way assisted in the death of Pauline that morning by his sister Ruth. Hm. It’s very delicately presented and credit, I expect, ought to be given to the programme’s legal department.

Ruth is not interviewed. Mansfield refused to be interviewed. The reporter who broke the best stories about the case, Carolyne Meng-Yee from the Herald, is not interviewed but is seen throughout Polk scurrying to and fro in a beautiful full-length winter coat. One person who has virtually nothing of interest to say but is interviewed at length is Julia Hartley-Moore.

You may remember Hartley-Moore from her constant media appearances talking about what incredible work she performs as a private investigator. If you have forgotten, Hartley-Moore appears on Polk to remind you about her incredible work as a private investigator. The show makes very generous use of her. She is the show’s executive producer.

Anyway she thinks Hanna called her not long before she died. It wasn’t a very long phone conversation and nothing much was said. Cut to Hartley-Moore saying of Remuera, “There’s a lot of money and a lot of secrets!” What?

After Pauline’s death, she worked hard to get an interview with Polkinghorne. He finally relented. “But,” she says, “I felt he didn’t respect women.” And so she arranged for a male journalist to conduct the interview. He isn’t named in the programme and when I asked director Mark McNeill, he said the journalist wished to remain anonymous.

The journalist is Chris Cooke, who worked on Sunday. Full credit to Cooke and Hartley-Moore for getting him on camera. Polkinghorne regards it as an opportunity to declare his innocence. Viewers are more likely to see a deplorable sex elf casually wandering around the house where his wife died in whichever version of agony.

An exquisite sensitivity attends every piece of footage of Hanna.

The show acts as a sweet memorial. Her family are thanked in the end credits. Polkinghorne, despite giving his time and his only interview, is not thanked.

“I think they’ll lose the case,” he says on camera. “I have no doubt about that.” He was 100% right. It’s one of the few times in his interview where he sounds confident.

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