3.3 Comparing the evidence

Figure 14

The evaluation of the statements shows that the evidence gathered by DS Sund did not fall into either of the ‘biased’ categories. This was because she did not ask leading questions that suggested a possible answer, did not let the witnesses talk to each other or hear one another’s statements, and was also careful to check estimates of height.

However, while DI Bullet finished by producing a summary containing a series of quite definite descriptions, that he got the witnesses to agree to, a great deal of the evidence gathered by DS Sund was conflicting. For example, Lila remembered a riot helmet being knocked off one of the robbers, while Seth remembered it being knocked from one of the guards. In addition, at one point Seth reported that one of the masked robbers grabbed Liz and at another that it was the driver. These discrepancies were particularly noticeable in the descriptions, while the evidence of what happened was more consistent. This can often be the case, because people tend to be more accurate at remembering actions than they are at providing detailed descriptions.

At first glance, it might appear as if DI Bullet’s evidence is more convincing, as it tells a straightforward and consistent story that is supported by statements from both witnesses, while DS Sund’s evidence is considerably more complex and inconsistent.

You’ll see how both investigations progress later in the course.