“And there are no other suspects?” Dave, I know, likes it when I make it sound like he is the whole force.

“Not at the moment, mate—Simon’s a violent man, he’d even tried to kidnap Grace when she was small and we know he was having money troubles, been on the dole for years, can’t hold down a job. Claimed it was because of mental health problems. There’s no doubt this was him.”

“What about forensics?” I can see the moisture from Dave’s pint on his bottom lip.

“Nothing’s come up yet. It was all planned. He wiped the lamp or was using gloves, and they’re saying he probably wasn’t wearing shoes—took them off so he didn’t make any noise. He knew what he was doing, that’s clear enough. The rest of the house is full of the girl’s and the victim’s DNA, plus quite a few other sources. We’re checking all their friends and neighbors when we speak to them.”

I nod.

“The phrase I like to use is ‘every contact leaves a trace.’” Dave pauses, to let the well-known police wisdom he’s claiming as his own sink in. I’ve heard it before, but I don’t tell him that. Dave raises a finger. “But the key thing to remember, Jon, is that the evidence might not be left at the scene. I call this ‘reverse contact.’ So the perp could have taken evidence of contact away with him. He might have traces of the victim’s DNA on the clothes he was wearing, for example.” Dave nods his head as he waits for me to take it on board. He should have been a teacher instead of a policeman.

“Sounds like Simon thought it all through carefully, especially for someone so mentally unstable.” I’ve always railed against assumptions of criminality, but Dave has confirmed what I already knew: there is no other possible suspect. Meg’s and Grace’s lives were so closeted—they weren’t involved in any shady dealings that might implicate them. Besides, I don’t want to make it sound like I’m defending Simon and risk making myself even more of a social pariah.

Dave shrugs. His eyes flicker towards the sports news that’s now on the TV as he says, “Apparently he’d go up and down. Must have planned all this on an up. If I’m honest with you, mate, he’d been suicidal before. I reckon he decided to take his daughter with him. It’s like what you said in the article—he didn’t think it was fair that Megan kept him from Grace. I think he wanted to punish Megan in the cruelest way he could think of for keeping him away.”

I hate that he’s saying the worst possibility out loud, as though the saying of it makes it more likely to be fact. Even worse, I hate my work being involved, albeit indirectly. I know the story already but I don’t want to lose Dave to the football so I say, “Remind me about the first time he tried to take Grace.” Dave fixes his eyes on me as he takes two big gulps of his pint, stifling a burp before replying.