‘Your fault?’

‘I told him what I suspected about the Negrita.’

The ship Sheepskin had mentioned on the flight to Sullom Voe; afterwards clamming up.

‘What happened?’

‘It was a few months back. You know Sullom Voe has some of the strictest procedures going? I mean, time was tankers would swill out their dirty bilges as they approached the coast – it saved pumping them ashore at the terminal … saved time, which meant money. We used to lose black guillemots, great northern divers, shags, eider ducks, even the otters. That doesn’t happen now – they tightened up. But mistakes still happen. That’s all the Negrita was, a mistake.’

‘An oil spill?’

Harley nodded. ‘Not a big one, not by the standards we’ve managed to set with Braer and Sea Empress. The first mate, who should have been in charge, was in the sick bay – bad hangover apparently. A crew member who hadn’t done the job before hit the wrong sequence of levers. The thing was, the crew member didn’t have any English. That’s not unusual these days: the officers might be British, but the hired help is the cheapest the company can get, which usually means Portuguese, Filipino, a hundred other nationalities. My guess is, the poor sod just didn’t understand the instructions.’

‘It was hushed up?’

Harley shrugged. ‘Never really news in the first place, not a big enough spill.’

Rebus frowned. ‘So what’s the problem?’

‘Like I say, I told Mitch the story …’

‘How did you know?’

‘The crew landed at the terminal. They were in the canteen. I got talking to one of them, he looked awful – I can speak a bit of Spanish. He told me he did it.’

Rebus nodded. ‘And Mitch?’

‘Well, Mitch found out something that had been covered up. Namely the tanker’s real owners. It’s not easy with these boats – they’re registered here, there and everywhere, leaving a real paper trail in their wake. Not always easy to get details from some of the registration ports. And sometimes the name on the papers doesn’t mean much – companies own other companies, more countries are involved …’

‘A real maze.’

‘Purposely so: a lot of the tankers out there are in shocking condition. But maritime law is international – even if we wanted to stop them landing, we couldn’t, not without the say-so of all the other signatories.’

‘Mitch found out that T-Bird Oil owned the tanker?’

‘How did you know?’

‘An educated guess.’

‘Well, that’s what he told me.’

‘And you think someone at T-Bird had him killed? But why? Like you say, it wasn’t a newsworthy spill.’

‘It would be with T-Bird in the frame. They’re going all out to persuade the government to let them dump their platforms at sea. They’re talking up the environment and their record in that area. We’re Mr Clean, so let us do what we want.’ Harley showed bright white teeth as he spoke, the words almost a sneer. ‘So tell me, Inspector, am I being paranoid? Just because Mitch gets thrown out of a window doesn’t mean he was assassinated, right?’