‘PTSD,’ Esson said now, shaking her head in disbelief. Somehow, without Clarke having noticed, the tepid tea had been switched for a fresh mug. She lifted it and took a slurp. Esson herself only ever seemed to drink hot water, at least while on duty. ‘It’ll never fly, will it?’

‘I don’t know,’ Clarke confessed. All Haggard had stated at the interview was that the job he’d been doing for the past fifteen years had left with him the condition.

‘My client is unwilling to go into details at this time,’ Leckie had commented, sounding as though he might not himself know too many of the particulars. Haggard had already been charged and was out on bail, with the stipulation that he not go within a couple of postcodes of his wife or their shared address. He’d been suspended from police duties, naturally, and interviewed several times as part of the investigation. Esson had been assigned to the case from the get-go, but Clarke had only come aboard when DC Ronnie Ogilvie, Esson’s usual CID partner, had caught COVID, leaving him isolating at home.

‘PTSD,’ Esson repeated.

‘I’ve been looking it up online,’ Clarke said. ‘It’s for battlefields and terror attacks. Surviving a tsunami or childhood trauma.’

‘He’s going to say a priest fiddled with him after choir practice, and thirty years later he’s battering his partner?’ Esson sounded sceptical. ‘Funny he’s only just decided that’s his mitigation. Pound to a penny some men’s group online will have suggested it. We should check if it’s been tried in the past. And we need to let a psychologist have a go at him.’

‘There’s a lot we need to do, Christine. Has he been stationed anywhere other than Tynecastle?’

‘A few relief shifts down the years. But otherwise, no.’

‘So this PTSD stems from working at Tynie.’

‘The dreaded Tynie. Suddenly it begins to look more plausible.’

Every cop in Edinburgh knew at least one story from Tynecastle. Officers there had a reputation for overstepping the mark and getting away with it. Countless prisoners had tripped on their way to or from its holding cells, or fallen down stairs, or somehow lost their balance and ended up planting their face into a wall. CCTV wouldn’t have been functioning at the time. Accusations of misconduct would be withdrawn or come to nothing. There were whispers, too, of larger misdeeds – manufactured evidence, cover-ups and bribes.

‘Her name’s Cheryl,’ Esson suddenly said.

‘What?’

‘Cheryl Haggard. The victim. We shouldn’t lose sight of her in all this.’

‘That’s a good point. If he’s been suffering from PTSD, wouldn’t she be the first to know? He’d have said something, wouldn’t he? Or she’d have sensed him changing.’

‘You’ve not spoken to her yet, have you?’