(c) Incorrect testimony of witnesses
Witnesses are by far the most unreliable means of evidence in criminal proceedings. Judges and public prosecutors are also aware of this. In practice, however, the necessary consequences are not always drawn from this finding.
Contrary to popular belief, a lying witness is not easily recognizable. For example, if someone is sitting on the witness chair and sweating, this is a normal reaction to an unpleasant and unfamiliar environment. Conversely, cold-blooded liars often give the impression of sovereignty and often even appear sympathetic. Even with the modern methods of science, it is practically impossible to tell whether a person is telling the truth by his behaviour, origin or history. Even lie detectors are regarded by the courts as inadmissible evidence – although they could (and should!) contribute in individual cases to save innocent people from an unjust conviction.
Witnesses who deliberately lie in court are the exception anyway. They are often unmasked – because their involvement cannot be reconciled with the objective facts.
The most reliable method of exposing false statements is content analysis and comparison with objective facts.
This also and especially applies in cases where witnesses unintentionally say the untruth. This happens much more often than one might think. The human brain is extremely error-prone. It therefore does not even require malicious suggestions or influence to produce false memories. These can also arise when, for example, a witness is under particular pressure.
In one experiment, an actor dressed in dark clothes ran out of a house. Several passers-by could see him. If one asked these passers-by whether they could describe the person who had just walked past them, the answer was usually that this was not possible. The witnesses told the truth: they had no reason to pay attention to the man passing by.
When the experiment was repeated in exactly the same constellation, the witnesses were asked the question:
“A child had just been killed in the house. The murderer ran past them here a minute ago. Can you describe him?”
Although it was documented by cameras that the passers-by had in reality paid no attention at all to the passing actor, the witnesses were now subjectively able to give detailed descriptions of the man – which did not correspond to reality at all!
The witnesses were sure they were doing something good. They did not realize that their memory was playing a trick on them. Instead of recalling “a film from memory,” the witnesses unconsciously activated memories from a corner of their brain. These images had absolutely nothing to do with reality.
Such failures of the human brain are often the cause of devastating wrong decisions by courts. A defence lawyer must work early and vigorously to ensure that false memories do not become the basis of a false conviction.