Specimen material is needed for any comparison process and, to have that material admitted into evidence, it must be ‘proven’ to a trier (i.e., judge or adjudicator) who decides whether not to admit the samples. Basically, this means the specimen samples must be shown, in some way, to have been produced by someone or something in particular. Adequate ‘proof’ of origin is necessary for them to be used, and relied upon, as examples of writing (or output) from a specific source.

This issue manifests whenever the matter proceeds to a trial or adjudication. However, knowing that this is a concern, and knowing that such information will have to be given as ‘proof’ of the history or origin of a document, consideration should always be given to it from the start of the process. There is no benefit to working with unproven or dubious material. In other words, the issue of ‘proof’ of source should be considered and addressed for every sample of specimen material used in any comparison.

So, who needs to do this? In brief, ’proof’ of a document must come from some other party, and not from the forensic document examiner, as a general rule. This issue is something the client, or their legal representative, should be considering as they collect or obtain specimen material for examination purposes.

How can a specimen sample be ‘proven’? Some ways to prove authorship of a document include:

1. simple admission by the author of the document when asked if they produced it;
2. testimony of someone who saw the writing done (i.e., a witness to the writing). This applies, for example, when obtaining specimen writing of a “request” nature;
3. testimony of someone who heard the writer admit that they wrote the document. This could be #1 above, but also applies in a more historical sense;
4. testimony of someone “intimately familiar” with a person’s writing (e.g., a husband, wife, or business partner may be able to provide such testimony for the other); or
5. as normal and accepted practice for any particular type of document. For example, business documents routinely prepared in the name of a person, or signed by that person, may generally be used as examples of their writing so long as the documents were produced in the normal course of business and have not been challenged in the past by the person named.

Remember: The client (investigator or lawyer) has the responsibility of providing proof of this nature to the court, through one of the above means. This often means that other witnesses will need to be called who can personally attest to the matter based on their personal knowledge. It is not the responsibility of the examiner to do this (unless, of course, the examiner was involved in the acquisition of the samples; e.g., obtaining request specimen samples).

Related questions:

• What is a specimen/exemplar?
• What purpose do specimen samples serve?
• What type of specimen samples do you need?
• How much specimen material is needed?