Key Points:

Leanne Cameron described Bruce Emery's impassive face as "painless".

"Sorry" wouldn't bring her 15-year-old son back, she railed, but then she complained that Emery had never apologised to her. He'd never sought her forgiveness for taking Pihema's life over "a bit of paint".

What she seemed to need was some sign of remorse, some indication that Emery regretted what he had done - that maybe he too was in turmoil.

What she got was a frozen mask that gave her nothing. He was "painless", she concluded - untouched by her pain, unmoved by the loss of her child's life. He showed too little emotion; she showed too much.

While she raged and wept in front of the cameras, Emery's remorse was filtered through his lawyer, Chris Comeskey. Since his sentencing, Emery has told the Sunday Star-Times that he is devastated. "There are a lot of days I cry over this. Every day I ask for forgiveness."

The pity of our criminal justice system, which places a legal and emotional wall between victims and offenders, is that this is not what Leanne Cameron and her family have seen or heard from Emery.

It might well have assuaged their anger and helped them to "move on", as Comeskey suggested they should, if they'd had the slightest hint from Emery that their boy's life meant something to him.

Why didn't they? Why was there not even a letter? Comeskey told reporters that Emery's bail conditions prevented contact with the Cameron family. If so, maybe it's time Emery rectified that. He might also, while he's at it, do us all a favour and restore some much-needed sanity by explaining to the misguided members of his fan club how sorry and stupid and un-heroic he feels. If the reaction of Pihema Cameron's family has been bitter and intemperate, the reaction from those keen to
pin a medal on Emery and make him the poster boy of vigilantism has been so lacking in humanity and what used to be common decency and civility that I wonder why we legitimise it by giving it space.

When did it become acceptable to cheer on the killing of a teenage boy as if he'd been a pest that deserved to be exterminated? When did the defacement of property become justifiable provocation for the kind of rage that ends in the death of a boy? And what are we sowing when we peddle this toxic mix of loathing and fear?

If we want a less trusting and connected society - fertile ground for more tragedies - we're headed in the right direction.

Emery is no hero; he cuts a rather pathetic figure. On the night of January 26, 2008, he was an enraged man who took a kitchen knife and chased two taggers more than 300m up the road after they'd tagged his garage. He said the stabbing was accidental, that he took the knife because he feared being attacked. But as Pihema lay bleeding at the scene, Emery walked home, washed the knife and hid it, saying nothing to anyone until the police questioned him.

The jury convicted him of manslaughter because they couldn't be sure that he intended to kill Pihema. I would probably have given Emery the benefit of the doubt, too. But was his sentence of 4 years 3 months too light?

After Emery's sentencing last week, Senior Sergeant Gary Lendrum told reporters that "when you boil it down, it was simply someone reacting to an injustice that they felt, and most homicides are that, people become angered by something that occurred to them and they react".

A QC said much the same thing in a Salvation Army report on prison policy: "From what I see people commit violent crime for three main reasons: spontaneous act, they are mentally ill, or provocation. Very few are doing planned premeditated violence."

In other words, Emery is where he is for the same reasons thousands of other people are in prison. He made some very bad choices in the heat of the moment, and a teenage boy died as a result.

Whether or not he intended that outcome is immaterial. The jury did not acquit him; it found him guilty of causing Pihema Cameron's death.

So it's difficult to understand why the likes of the Sensible Sentencing Trust's Garth McVicar is so keen for Emery to avoid prison. Such understanding and compassion isn't usually extended to other convicted killers, but perhaps this illustrates the difference it makes when the person involved is someone McVicar can more easily empathise with - a white, middle-aged middle-class businessman.

I'm not a proponent of longer prison sentences for the sake of it. Unlike the hardline lock'em up brigade, I've never regarded prison as a "soft" option. Four years cannot possibly reflect the value that society puts on a life, but it's a long time to be deprived of your freedom. Emery should serve his time and be grateful it's not longer. His expressions of remorse will mean little if he appeals and seeks a sentence that attempts to diminish his culpability.