“Got himself shot in a drug war with the Jamaicans in 1982.”

“But he never did time?”

“Never got charged with anything, far as I remember.”

“Doesn’t that strike you as odd, sir?”

“Odd?” Shaw seemed to snap out of his reminiscing mood and become his grumpy old self again. He stuck his face so close to hers that she could smell his tobacco-mint-and-whiskey breath and see the lattice of purple veins throbbing in his bulbous nose. “I’ll tell you what’s bloody odd, DI Hart. It’s you asking these questions. That’s what’s odd. None of this can possibly have anything to do with what happened to Graham Marshall, and that’s a fact. You’re muckraking. I don’t know why, but that’s what you’re doing.”

“Sir, all I’m doing is trying to get a handle on the circumstances of the boy’s disappearance. Looking over the investigation and over other investigations around the same time seems a reasonable way of doing it to me.”

“It’s not your brief to look into the Marshall investigation, DI Hart, or any other, for that matter. Who do you think you are, Complaints and Discipline? Stick to your job.”

“But sir, Bill Marshall was one of the men interviewed in connection with this protection racket, all involved with Carlo Fiorino and Le Phonographe. Some of the city center shopkeepers filed a complaint, and Marshall was one of the people they named.”

“Was he charged?”

“No, sir. Only questioned. One of the original complainants ended up in hospital and the other witnesses backed off, retracted their statements. No further action.”

Shaw smirked. “Then it’s hardly relevant, is it?”

“But doesn’t it seem odd to you that no further action was taken? And that when Graham Marshall disappeared, his father never came under close scrutiny, even though he had recently been implicated in a criminal ring?”

“Why should he? Maybe he didn’t do it. Did that thought ever enter your head? And even if he was involved in some petty protection racket, it doesn’t make him a child killer, does it? Even by your standards that’s a long stretch of the imagination.”

“Was Bill Marshall a police informer?”

“He might have let slip the odd snippet of information. That’s how we played the game back then. Tit for tat.”

“Is that why he was protected from prosecution?”

“How the hell should I know? If you’ve read your paperwork, you’ll know I wasn’t on that case.” He took a deep breath, then seemed to relax and soften his tone. “Look,” he said, “policing was different back then. There was more give-and-take.”

Plenty of take, Michelle thought. She’d heard stories of the old days, of departments, of stations and even of whole counties run wild. But she didn’t say anything.

“So we bent the rules every now and then,” Shaw continued. “Grow up. Welcome to the real world.”

Michelle made a mental note about Bill Marshall’s possible role as a police informer. If he had informed on criminals here in Peterborough, she could only imagine what the Krays might have done if he’d tried anything like that with them and then disappeared. The South Pole wouldn’t have been far enough, let alone Peterborough. “From what I can piece together,” she went on, “the Graham Marshall investigation followed one line of inquiry and one only when it became clear that he hadn’t run away from home: a sex killing by a passing pervert.”