With a long thin stainless steel implement, Elsa gently prised open the mouth of Mahmud Irani. Then she did the same with Hector Welles, and finally Darren Donovan.
‘See that?’ Elsa said, her blue eyes bright. ‘When a man has been hanged, his tongue turns purple.’
Dr Joe had begun to pant like a dog on a summer’s day.
‘I’m OK,’ he said, not looking at me. ‘I’m fine. Really.’
‘This is how strangulation by hanging works,’ Elsa continued. ‘Once the noose is around your neck and there is nothing to support you, you are killed by your own body weight. Strangulation compresses the carotid arteries in the neck, shutting off the supply of blood to the brain and causing the brain to swell so much that it plugs the top of the spinal column. This causes a reaction known as the vagal reflex, which stops the heart. The compression of the neck closes the trachea and aborts the supply of oxygen to the lungs. So – no blood to the brain and no air to the lungs. Bad news. The victim passes out due to suffocation. And then he dies.’
‘How long does it take, Elsa?’ I asked.
‘It depends. But it is not a quick way to die. Strangulation by hanging takes at least five minutes, but no more than twenty.’
‘Do we have any defensive wounds?’
‘There are no defensive wounds on Mahmud Irani or Darren Donovan, although there are signs of advanced intravenous drug use on Mr Donovan.’
‘What does advanced mean?’ Dr Joe asked.
‘The veins of his arms had collapsed and he was shooting up between his toes,’ Elsa said. ‘But Hector Welles is the only one of them with extensive defensive wounds.’
I remembered Welles fighting for his life as the dark figures struggled to control him.
He knew what they had done to Mahmud Irani.
‘There are contusions and welts on Mr Welles’ arms where he was restrained,’ Elsa said. ‘Some facial bruising where he was punched or kicked.’ She smiled sadly at me. ‘But unfortunately no skin tissue under his fingernails, Max. Apart from his own.’
In the glare of the Iain West, the flayed neck of Hector Welles looked like the self-inflicted scars of some bizarre tribal ritual.
‘Hanging is of course a popular method of suicide. But Mr Irani and Mr Donovan both have burn marks on their wrists where their hands were secured behind their backs, precluding suicide. Mr Welles did not have his hands secured behind his back, making suicide a theoretical possibility – in fact, most suicide hangings look exactly like Mr Welles, as they change their mind when it is far too late and attempt to claw the noose from their neck. But the extent of his defensive wounds eliminates that.’
‘And three million hits on YouTube of the guy being hanged,’ Edie said.
Elsa Olsen looked at her sharply.
‘I’m looking at the medical evidence and not what’s trending on YouTube, Detective.’
‘Of course,’ Edie said.
Elsa nodded curtly. ‘And a suicide victim is unlikely to be cut down and dumped in the middle of Marble Arch. The dead don’t move themselves,’ she said. ‘In all three cases, the manner of death was murder.’
‘Anything you can give us about the knot?’ I said.
The way a knot is tied and the type of knot used might have been a priceless lead, I thought, remembering Pat Whitestone’s words when we had found Mahmud Irani. But Elsa shook her head.
‘Sorry,’ she said. ‘For that I would need to see the rope or the wire or whatever it was. The neck markings are not enough to go on.’
‘We still don’t have a kill site, Elsa,’ I said. ‘How long had they been dead when we found them?’
‘They’re all different. As you know, rigor mortis sets in after approximately two hours and then the body gets progressively stiffer. And then we follow the twelve-twelve-twelve equation. Twelve hours to get stiff. Twelve hours to remain stiff. And twelve hours for the body to lose that stiffness as it begins to decay. Rigor mortis had just begun to set in on Mr Irani, suggesting he had been dead for around twelve hours when he was discovered. The second victim, Mr Welles, had advanced rigor mortis. He had been dead for approximately twenty-four hours. And the body of the latest victim, young Mr Donovan, was losing the stiffness of rigor mortis. And you can see that his skin has a greenish hue around his head, shoulders and abdomen. There’s also a degree of bloating because of gases accumulating in the cavities. His internal organs had longer to break down.’
‘Because the bodies are becoming harder for us to find,’ I said.
‘And there’s lividity on the back of Mr Irani,’ Elsa said, nodding at Edie. ‘Would you be so kind, DC Wren?’
Together the two women turned the cadaver of Mahmud Irani onto his front. The skin around his shoulder blades, back, buttocks and calf muscles was pale and surrounded by ugly purple blotches that looked like bruises. Dr Joe looked at me.
‘That’s the lividity,’ I said. ‘Those marks that look like bruises. Think of lividity as stagnant blood. When you die, your heart stops beating and your blood stops moving. Gravity does the rest. The blood settles. But you don’t get it where the body touches the ground. Lividity can help us determine how long someone has been dead and if the body has been moved.’
‘The technical name is livor mortis,’ Elsa said.
‘From the Latin,’ Dr Joe said. ‘Livor meaning bluish and mortis meaning of death.’
Elsa and Edie heaved the dead man onto his back.
‘The lividity on Mr Irani strongly suggests that he lay undisturbed for most of the time between death and discovery,’ Elsa said.
‘What does that mean?’ asked Dr Joe.
‘It means they didn’t move him very far,’ I said. ‘So the kill site has to be within – what? – one hour’s distance of Marble Arch and Vauxhall Bridge.’
‘That narrows it down to all of Greater London,’ Edie said.
‘I can also tell you they were all taken down minutes after death,’ Elsa said. ‘If they had been left hanging, the furrow of the neck wounds would be much deeper.’
We stared in silence at the bodies. I felt myself shudder.
It’s just the cold, I told myself. Just the bitter cold in here.
‘And there’s something else,’ Elsa said. ‘A professional hangman works on a system of variable drops. It was the method used by this country’s most famous executioner – Albert Pierrepoint. Saddam Hussein’s goons used the same method. How heavy the body is, how far it needs to fall to separate the second and third vertebrae in the neck and cause instant death. It’s called the hangman’s fracture. If the drop is too long, the victim is decapitated. These people – the Hanging Club – clearly don’t bother with variable drops. Despite the charade of hanging, they essentially strangle their victims.’
She gave Edie Wren a severe look.
‘And I watch YouTube, too,’ Elsa said. ‘But what’s interesting is that the most recent victim appears to have died in less than half the time of the first two. Examining the damage to the carotid arteries and the spinal column, I estimate that Mr Irani took thirteen minutes to die, Mr Welles took ten and Mr Donovan took just five.’
‘What does that mean?’ asked Dr Joe.
‘It means they’re getting good at it,’ I said.
We were back in the changing room, taking off our scrubs, when Dr Joe began talking about signatures.
‘The three murders are more than ritualistic killings,’ he said, pulling off his hairnet. ‘Among the unknown subs there’s a clear hierarchical structure at work.’
‘Yes, it’s always the same one who asks the question,’ I said. ‘Do you know why you’ve been brought to this place of execution? He’s the leader.’
‘Everyone has their role to play and yet they are capable of acting in the interests of the group,’ Dr Joe said.