as the duke, opening the shutters. They assumed that he too had heard the noise of the burglars and rushed into his wife’s bedroom to deal with them. The servants went back inside to go to the duke’s aid. To their surprise, the bedroom door was now open. The duchess’s room was in a state of chaos; furniture had been overturned and there were splashes of blood on the walls. They saw the duchess herself sitting on the floor, propped against her bed, evidently dead. Her face was battered and bruised. Her throat had been cut.
While the stunned servants were examining and taking in this appalling sight, the duke walked in and cried out as he saw his dead wife. ‘Some monster has murdered my beloved Fanny! Fetch a doctor.’ He said he had only just been woken up by the noise. The servants knew better; they had seen him at the window a few minutes before.
Two policemen passing in the street noticed that the front door was open, which was unusual, and decided to come in to investigate. Before long the house in the Rue Faubourg St Honoré was overflowing with policemen. Among them was Monsieur Allard, head of the Sureté. He rejected the burglar theory almost at once. If the place had been burgled, why did the burglars leave the duchess’s jewels? He also found a Corsican pistol underneath the sofa; it was covered in blood. Allard asked the obvious question; ‘Does anyone know who this pistol belongs to?’ He was very surprised by the answer. The duke said, ‘Yes, to me’.
Allard asked the duke how the pistol had got there. The duke said he had heard cries for help and rushed to his wife’s bedroom waving his pistol. Seeing that she had been attacked and was covered in blood, he had dropped his pistol to raise her up. In consequence, he too had become covered in blood. Then he realised his wife was dead, so he went back to his own bedroom to wash off the blood. It was just about possible, but he had already told the servants that he had only that moment woken up, and he had also cried out in pretended surprise when he had come into the room after the servants arrived.
Allard went next to the duke’s bedroom and pointed out that the trail of blood splashes and stains led to his door. The duke explained that he had been dripping with his wife’s blood as he had returned to wash. But then there was further evidence in the duke’s bedroom. There was a bloodstained handkerchief, the bloodstained hilt of a dagger, and a piece of bloodstained cord. Then Allard found the severed end of the bell-cord from the duchess’s bedroom hidden inside the duke’s shirt. At this point, Monsieur Allard arrested the duke for his wife’s murder.
There was the strong possibility that the duke would persist with his version of events. It would be very difficult to prove that what he was saying was untrue – even though Allard and the duke’s own servants all knew the duke was lying. It might well be that the case could not be made to stand up in court. He could claim that the servants in their confused and emotional state had misunderstood what he had said about when he was awakened. Even the severed bell-pull could be explained as an irrational, deranged response to the trauma of finding his wife savagely murdered. No-one in court might believe his fabrication, and yet it might still be impossible to get a conviction.
Then another key figure came into the story – a brilliant pioneering forensic scientist. Ambroise Tardieu had written the first scientific treatise on hanging. He had also discovered the ‘Tardieu spots’, the spots of blood that form under the hearts of people who have been suffocated. What M. Allard wanted to find out was whether the pistol had been dropped in the duchess’s blood, as the duke claimed, or actually been used as a murder weapon. Tardieu approached the problem with characteristic thoroughness. He studied the pistol with a magnifying glass, then under a microscope. He found a chestnut coloured hair