Obtaining Known Genuine Signature Specimens
The average problem of signature identification normally requires a minimum of fifteen to twenty known genuine signatures for comparison with a signature that is unknown or disputed. However, many problems of signature identification necessitate a greater number of known specimens for one or more reasons.
It is equally important for a document examiner to have not only a sufficient quantity of known standards for comparison purposes, but to also have the right quality of known standards. For example, fifty genuine signatures on gasoline credit card receipts may be worthless when used for comparison with a questioned signature on a last will and testament, whereas only five genuine signatures on legal documents might prove quite satisfactory.
It is suggested that when obtaining known comparison signatures, the investigator consider the circumstances listed below in order of importance:
- Genuine signatures written nearest in date to the date of the questioned signature.
- Genuine signatures written on similar material (checks, unlined stationary, similar printed forms, etc.).
- Genuine signatures written under the same alleged or known circumstances.
- Genuine writing written with a similar writing instrument (ball point pen, roller ball pen, fountain pen, pencil, etc.).
- Often times canceled checks are of assistance, particularly because they have confirmed dates. If possible, canceled checks should be submitted in sequentially numbered groups of fifteen or more.