2.1 Everyday fact-finding

Fact-finding is something that people do day-in, day-out with such ease that they rarely think about it. Fact-finding is a type of inference. Inference is where we draw conclusions by combining evidence that we hear or see with existing knowledge. For example, when a person’s mobile phone alarm goes off (evidence) and even before they open their eyes, they infer that it is 7 a.m., (fact) on the basis that that is the time the alarm always goes off. And if there is a knock at the door (evidence) they infer before opening the door that it is a delivery (fact) because they are expecting a parcel and not a visitor.

Figure 2 In everyday life, people infer facts from evidence such as: (a) a mobile alarm or (b) the sound of a knock at the door

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(a) Person sleeping next to their phone; (b) Person knocking at the door.

Figure 2 In everyday life, people infer facts from evidence such as: (a) a mobile alarm or (b) the sound of a knock at the door

Figure 3 Using evidence and existing knowledge to infer facts

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A diagram in two parts. The first shos two arrows pointing to a central tile. The arrows show people use evidence (their alarm going off, or the sound of a knock at the door). Arrow 2 shows existing knowledge (that their alarm always goes off at 7 a.m., or an expectation of a delivery). These arrows point to the central square, to indicate an inference of facts (that it is 7 a.m., or that the delivery driver must be at the door).

Figure 3 Using evidence and existing knowledge to infer facts

Notice that the factual inferences are never certain. If you imagine a scale from 0 to 100% where 0% is impossible, 50% is evenly balanced, and 100% is absolute certainty, all factual inferences will fall somewhere along that scale (see Figure 4). When the alarm goes off, the person might think it 99% certain that it is 7a.m., but they could be wrong. Their dastardly housemate might have changed the time, they might have forgotten that the clocks went back, or they may have pressed the ‘snooze’ button earlier. They might infer that it is 80% likely that the knock on the door is the delivery driver, but perhaps it is instead a neighbour who has locked himself out of his flat, or a group of police officers coming to arrest him for that jewellery heist in the 1970s he thought he had got away with.

Figure 4 Scale of probabilities

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A diagram that shows the probability of different events. It shows a scale from impossible on the left to certain on the right. Events are labelled above the scale, and the corresponding percentage probability is shown below the scale. The probabilities and events shown are: the probability that a clover has four leaves is 0.01 per cent; the probability of getting struck by lightning is 0.0033 per cent; the probability a person is left-handed is 10 per cent; the probability that it will rain on a given day in the UK is 33 per cent; the probability of a fair coin toss landing on tails is 50 per cent; the probability that a baby will be a boy is 51 per cent; the probability of surviving an aeroplane crash is 95 per cent.

Figure 4 Scale of probabilities

In the next section, you will see how legal fact-finding is similar to everyday fact-finding.