Whodunnit?4.13 What evidence can we use to solve a crime?

This is a small country house near the Dart River on the Devon–Cornwall border. It has 15 bedrooms, 5 reception rooms and a complete wing which stores the owner’s collection of knives and swords. At a house party organised for sword collectors, Sir Gilbert George-Montgomery was found murdered. Suspicion fell on the other guests … but who did such a terrible thing?

The murder! Sir Gilbert was found in the boathouse with an antique samurai sword embedded in his chest. The sword itself was familiar to all the guests – they had handled it earlier in the evening. The police surgeon established the time of death at just after midnight when all the guests claimed to be asleep in bed. But someone had left the house, crossed the rough grassy meadow and crept along the wet muddy river bank to kill their host! What evidence would you collect?

The guests Marcus O’Brien – an ex-army man and excellent swordsman. Part of his collection of swords is being auctioned off to pay gambling debts. Eli Gerrard – made his money from selling coloured water as herbal medicine. Extremely wealthy and Sir Gilbert’s greatest rival in the blade-collecting world. Sister Geraldine – present as an observer. Opposed to violence and weapons-collecting on religious grounds she will be reporting back to her order on the weekend’s events. Mrs Lettuce – married six times with a habit of losing her husbands to an early death or divorce lawyers. Mrs Lettuce is a woman to watch. Definitely don’t turn your back on her. Prof. Cruett – an expert in the field of authentication. Prof. Cruett is the man you need to convince if you want the knife- collecting world to believe that that rusty old knife really is from fourteenth century Kurdistan. He is a powerful figure.

Fingerprints on the sword handle Footprints in mud near the boathouse The path leading to the boathouse Fragments of skin under Sir Gilbert’s fingernails A small button in Sir Gilbert’s hand How many clues do you need before you can name the murderer? Examine the evidence in the following slides to make your decision.

Footprints in mud near the boathouse These footprints are new. It had rained heavily only a few days ago and so previous prints were washed away. Now it has been dry, these footprints could have been created at any time in the last few days. They look like boots rather than shoes and probably come from a man rather than a woman. What does this evidence prove? How could it be checked?

Fragments of skin under Sir Gilbert’s fingernails It looks as though Sir Gilbert put up a bit of a fight. Forensic officers have taken away some of the skin cells to try to match them to one of the suspects. At the moment both Prof. Cruett and Sister Geraldine have scratches on their face. The professor blames shaving and Sister Geraldine claims a bramble scratched her when she was walking along the riverbank. What does this evidence prove? How could it be checked? How will the DNA testing of the skin change the situation?

A small button in Sir Gilbert’s hand This matches a button on Sister Geraldine’s top. What does this evidence prove?

The path leading to the boathouse The boathouse has a path to it, which runs from the house along the river for a short distance. A road also passes next to the boathouse on the other side, which means deliveries can be dropped off just outside the door. What does this evidence prove?

Fingerprints on the sword handle The sword handle has prints from Sir Gilbert, Eli Gerrard, Prof. Cruett, Sister Geraldine and Mrs Lettuce. What does this evidence prove?

So whodunnit? And how confident are you that the evidence here is enough to prove their guilt? Some evidence is probably irrelevant. Some is missing. Are you prepared to name the culprit and explain what the evidence collected actually means? Let’s see who the real murderer is and the evidence that will convict.

It was Sister Geraldine Her fingerprints were on the sword but because she was opposed to weapons collecting she had not handled it during the evening. Sir Gilbert also had a button from her coat in his hand. She got to the boathouse by the tarmac road and so had left no footprints. When the skin under Sir Gilbert’s nails is DNA fingerprinted it will confirm that it came from Sister Geraldine. Marcus O’Brien had visited Sir Gilbert in the boathouse trying to sell some of his sword collection. Prof. Cruett cut himself shaving.