Murder Notes

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A maid working in a hotel recognises one of the guests as a businessman who got her fired from her dream job some years before. The hotel, quite a high class place, provides toothpaste, toothbrushes, towels, soap etc in each suite's bathroom.

She takes the toothbrushes from the businessman's room, soaks the bristles in a poison, and replaces the brushes. The plan is for the businessman and his family to brush their teeth in the morning, and several hours later to be dead. The maid would replace the toothbrushes with ordinary ones in the course of her normal duties, disposing of the poisoned brushes, hopefully leaving no clue as to how the poison got into their bodies.

However, the businessman gets an unexpected urgent call, and jets off with his family the night before they were supposed to use the toothbrushes.

Another family arrive, but due to booking mix-up, their rooms are unavailable. They are given the businessman's room for the night, and use the toothbrushes in the morning. The maid didn't see the businessman leave, and didn't know about the new family or the booking mix-up.

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"If you're a detective, sooner or later you'll screw up and get the wrong man convicted. If you think it'll never happen to you, if you think you're too good to let it happen to you, you're in the wrong job. If you can't live with the possibility, don't do the job. If it doesn't bother you, go somewhere else.

You want to know when I got the wrong man? It was a simple case of a young girl who'd drowned in a swimming pool. It looked like a straightforward accidental death - she'd left most of her clothes by the poolside, dived in, got into difficulty and drowned.

But there was no towel with the clothes. Why would someone go swimming and not bring a towel? It had to be murder.

Her father couldn't account for where he was when she died, and he'd been warned about hitting her about before. So we brought him in, pressured him and he confessed.

Then we found he was miles away when his daughter died, in bed with his girlfriend. The daughter really had just forgotten to bring a towel.

But we couldn't let the man go. He'd hanged himself in his cell the night before."

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The major clue in an investigation is what seems to be a diary kept by the killer. It details his thoughts about killing various people, including possible methods of killing and of avoiding detection.

The author of the diary is in fact the victim, who had been a fantasist, constantly imagining himself as murderer, plotting perfect crimes he was never going to commit. His own death was a coincidence.

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Problem: A husband and wife are found dead in their home, Both have been poisoned by the last meal they shared. There is no way the food could have been accidentally poisoned.

There is a marked empty test tube on the floor, and another one, unmarked, in the husband's pocket. Forensics show they contained the poison. They have the husband's fingerprints on them. It looks like the husband put poison into the meal, and they both ate it. A suicide pact?

The couple had an estranged son, a chemist. He had access to the poison, but had no way to get it into the food. He was in another country for a full month before they died.

The son claims (and others verify) that his father had visited him at the lab some months earlier, looking for a reconciliation, but it didn't work out. Could the father have stolen some poison then?

Solution: The husband had approached the son, asking for help in killing his wife. He could hardly cook his wife a meal and then not eat himself, and if she died of poisoning and he was unscathed, he would be the obvious suspect.

But, what if she died of the poison, and he showed symptoms of poisoning but survived, as though someone had tried to kill them both? What if, after making sure his wife was dead, he called an ambulence for both of them, and his bloodstream and stomach contents showed traces of the poison? That would shift suspicion away from him, and he could dispose of the test tubes before the ambulence arrived.

So all he has to do is poison the food, ensure he and his wife both eat it, and make sure she eats more. As a precaution, he should also carry the antidote, in case he accidentally ingests too much.

But, instead of giving the husband one tube of poison and one (marked) of antidote, the son gives him two tubes of poison. So when the husband gets crippling cramp and thinks he's eaten too much, he takes the "antidote", and poisons himself more.

The unmarked tube is still in his pocket, and the last thing he does is drop the marked one.

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A police detective investigating the death of a colleague is hampered by all the suspects being other members of CID. The police close ranks to protect their own - even when it's a murderer they're protecting, and even when they don't know which of their number they're protecting.

In the end, the detective finds the killer, but tells no one because he can't prove it. His superior tells him to drop the case - so as not to bring the name of the police into disrepute.

The hero gets the opportunity to kill the murderer undetectably. Would the investigator of that crime be similarly hampered?

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