Technically speaking, evidence is an object or piece of information aiming to prove the veracity, or at least high probability, of a particular claim. Not all pieces of evidence are created equal. In science as well as in jurisprudence, there exists a general hierarchy of the types of evidence, ranked by their ability to prove the truthfulness of a claim. Traditionally, there are five categories of evidence – listed below, from strongest to weakest.
- physical evidence
- documental evidence
- witness evidence
- party testimony
This concerns mainly rules of argument, among them the proper application of mathematical rules, but also more basic rules. For instance, we agree that two contradictory claims cannot be true at the same time, hence at least one must be false (and both could be false). This is called the Law of Non-Contradiction, and it has been accepted as valid since the time of Aristotle.
Another important logical rule is this: we are not allowed to posit a hypothesis that is defined in such a way that it is impossible to verify or refute. Therefore, anything we claim must, in principle, be open to verification or refutation. For instance, claiming “The Nazis murdered six million Jews and destroyed all the evidence” is a hypothesis that is immune to verification or refutation because the claim includes the assertion that there is no evidence; in other words, it is a self-serving or self-validating assertion, which is therefore meaningless. Worse, someone could make such a claim and then, when confronted with a lack of evidence (for the Six Million, for example), they may say, “Yes, this is exactly what my hypothesis claims, and thus it is true!” But this is nonsense. The claim is logically meaningless.
Physical evidence consists of material traces, objects, or physical remains supporting a claim. Apart from rules of logic, this type of evidence is generally regarded as the most reliable evidence, superior to all others. Speaking of crimes, this includes traces of victims (bodily remains), perpetrators, crime weapons and of the events and actions connected to a crime. Such traces often require the analysis and interpretation of experts, commonly involving advanced technical methods. While analytical data produced by technological means can be considered reliable, choosing the best method of analysis and interpreting the results properly depends on human judgement, where errors and malfeasance can come into play.
Documental evidence concerns information of any kind recorded on some physical medium. It consists of a physical part – the data carrier (paper, film, magnetic or electronic devices etc.) – and an information part, encoded in some form (writing, numbers, digital code etc.). A document is more reliable if fewer people were involved with creating it, or if it is less susceptible to manipulation. For instance, an automatically recorded footage on emulsion film has barely any human factor involved and is difficult to manipulate (in contrast to digital recordings), thus probably records events accurately, whereas a text typed on paper written by a human can contain just about anything, independent of the truth.
The physical part of the document can be subjected to analysis like every piece of physical evidence, whereas the informational part requires proper interpretation. Before a document can acquire probative value, it must be proven that the document is genuine and its contents factually correct. In order to establish this, factual evidence is again required to establish the authenticity and accuracy of the document. Moreover, a document has a higher probative value if it was created at a time when a contentious issue was not yet in dispute. This is particularly true for written bureaucratic documents during wartime.
A claim cannot be its own evidence. If a person claims that an event took place and claims also that s/he witnessed it, this does not make it evidence; it merely makes it a set of two claims, each of which still needs to be demonstrated to be true. In courts of law, however, witness testimony is often accepted as evidence for itself, which has led to countless travesties of justice worldwide for as long as courts have existed.
Witness testimony is a very unreliable way of trying to prove anything for numerous reasons, not the least because human memory is unreliable and easily manipulated, and because the tendency of humans to tell only half-truths or lie outright is legendary. The more a person is emotionally involved in a claimed event, the more likely it is that his or her testimony will be unreliable. Furthermore, the more an event is made the object of discussion in mass media and society at large, the more likely it is that genuine memory is replaced with later impressions from these secondary sources. There is currently no subject where these outside influences are stronger than when it comes to events of the Holocaust, because it is the most-thematized historical subject worldwide. Moreover, it is the only event where dissent from a given narrative commonly leads to massive societal pressure, if not outright persecution, and even prosecution in numerous countries.
If a person is a party in a dispute – such as an (alleged) victim or perpetrator – s/he should not even be considered a witness but merely a party. Party testimony, which is a subset of witness testimony, usually is the most unreliable kind of testimony, and should be seen at best as circumstantial indicators, since parties have an interest in incriminating the other party and exonerating themselves – all the more so during or after an atrocious war. In case of dogmatic societal or judicial situations, where the event in question is considered “self-evident” by the general public and/or the courts – as with the Holocaust – party testimonies from alleged perpetrators become almost worthless, as these are very often made not for reasons of honesty, but in order to gain advantages or benefits. This is especially true for claimed events of the Holocaust, where the alleged crime is cast in stone, the circle of possible perpetrators is determined beforehand, and only guilt and punishment remain to be meted out. In such a situation, contesting the reality of “self-evident” claims would only lead to an aggravated punishment.
Therefore, admitting the general, non-contestable historical charge as true while attempting to incriminating others and simultaneously trying to exonerate oneself is quite common. Such admissions of the general veracity of the overarching claims are therefore no evidence of their truth, but only hallmarks of corrupted legal procedures within a close-minded, intolerant society. The bottom line is that, with the Holocaust, claims by members of any victim group on the one hand, and of any perpetrator group on the other hand, are the weakest and most dubious forms of evidence.
See the list of witnesses in that entry. For a general overview of Holocaust evidence, see Section 5 “Evidence” in the entry on the Holocaust. For a general overview of Holocaust evidence, see Section 5 “Evidence” in the entry on the Holocaust.
Evidence needs to be evaluated as to its reliability, accuracy and authenticity. Furthermore, those who create, maintain or interpret evidence need to be evaluated for their trustworthiness. To learn more about the principles of source criticism and its impact on Holocaust studies, see the entry dedicated to this topic.