Oscar Lynch, the Crown fire expert Mum said should be a suspect, had migrated from Channel 7 to the witness stand. Describing the fire’s prologue of dry leaves, its turning point where flames took hold, he worked on igniting Nina’s emotions the way he’d ignite a future jury, with impossible-sounding facts and figures. 1200 degrees, 80,000 kilowatts a metre, 280C as the burning point for organic matter, traces of accelerants. Flames were characters with needs: fuel, heat, oxygen. Their enemies were investigators who understood the visual impact of lightning on bark, how to find traces of accelerants, the speed of a rider on a bike. But the flames themselves found allies in arsonists with petrol and kerosene, and in the trees.

‘Trees here need fire. Mountain ash lose bark in long ribbons that curl and become aerodynamic. They fly through the air while they’re alight.’

Douglas questioned him. ‘Did your investigation find any accelerants?’

‘No. An intense, fast-moving fire burns the evidence of its own ignition.’

‘Your statement says you began seriously investigating arson after hearing a disturbed juvenile with violent tendencies had been in the vicinity. Did you look for alternative sources of ignition? You’ve considered the likely impact of global warming? Fallen electrical wires? Lightning strikes?’

‘It was arson.’

He was so sure.

It was even harder to see the next witnesses come to the stand: neighbours. Mary Ross, who’d continued wishing Caleb a cheerful, ‘Good morning, young man!’ even after the accident. Caleb used to mow her lawn to earn money for his Scouts group.

‘I saw Caleb riding his bicycle up and down,’ she said now. ‘He said he was looking for smoke. Like he knew it was coming.’ Not even a ghost remained of the woman handing him twenty dollars. She, like Good Caleb, might never have existed. ‘I saw him at the relief centre. I asked him what he’d been doing. He said he went to help a friend. I knew he was lying. He has no friends.’

Caleb sank, diminished.

The prosecution case was over. Nina Haynes tapped a sheaf of papers on her bench. ‘Mr Wharton, you understand our purpose here? I could dismiss this case now if satisfied that no jury would convict you.’

Caleb clutched his knees until his knuckles ached. The magistrate was learned and wise. Might she see the truth? Mum was between Dad and Grandma. Nearby, Jack gazed at Caleb with a profound expression of affection, hope and understanding. These people loved him. All they wanted was for him to be cleared. They were deluded. Could he ever stop disappointing them?

Nina drew a long, slow breath. ‘However, I’m satisfied that a properly instructed jury could find you guilty. Therefore you do have a case to answer.’

Pain shot through Caleb’s fingers. He wouldn’t meet Douglas’s eye. Or Mum’s. She would think she’d once again let Caleb down. She began to cry. Would Caleb ever satisfy her?