For an initial enquiry about a signature, a description of the document and information about what you have will often suffice. However, the actual examination may require access to the paper original. State in your enquiry whether you have the original, a scan, a photocopy or a photograph sent by someone else. This difference affects the possible scope of analysis and how the conclusions are worded.
First identify the specific writing and question
A document may contain several signatures, initials on successive pages and handwritten additions. State which element is in doubt, which page it appears on and whose handwriting it should be compared with. A helpful description is: ‘the signature in the borrower’s field on the last page of the agreement’. The instruction ‘please check the agreement’ leaves too many possible directions for the examination.
Also clarify whether the question concerns who wrote the signature, alteration of the document or how a signature image was placed in a file. Establishing who made an entry and establishing how it came to appear on a particular document may require different actions.
What does access to the original offer?
ENFSI recommends examining original documents where possible. A copy may limit assessment of line quality and other characteristics of how the writing was produced. However, the guidelines allow work with non-original material, taking its limitations into account. Having a scan therefore does not, by itself, determine either the material's suitability or whether a conclusive answer can be obtained. [1]
If the original is in the case files, at a bank or held by the other party, say so immediately. You do not need to obtain it at any cost first. The starting point can be to determine which questions can be assessed using the available copy and whether a later stage will require access to the original through an agreed procedure.
How should a scan or photograph be described?
Before sending a file, prepare brief information about its origin:
- who made the scan or photograph and when, if known;
- whether the reproduction was made directly from the original;
- whether the file covers the whole document and all pages;
- whether the image was cropped, enhanced, printed or rescanned;
- whether an earlier file of better quality exists.
If you received only part of a page, preserve it while also exploring whether a complete reproduction can be obtained. Do not enlarge the image using software that invents details. Identify the filename in your message and describe the disputed area in words. Markings, arrows and comments can be prepared in a separate illustrative copy while preserving the file received from the source.
A signature in an image does not explain the document’s entire history
NIST highlights the possibility of transferring signature images between documents. Even resemblance to a person’s signatures does not automatically answer whether they signed this particular document. Conclusions must be limited to the examined material and the question posed. [2]
For example, you have a PDF contract sent by email and earlier paper documents bearing signatures. In your enquiry, it is useful to separate two issues: comparing the visible signature and assessing whether the file can be examined. State whether the message to which the document was attached has been preserved. Do not claim that the PDF is a scan of a paper original if you do not know how it was created.
A tablet signature requires separate clarification
In some systems, a signature made with a stylus is stored together with data describing the movement. A printout or ordinary image of the signature may not contain these data. The Institute of Forensic Research describes biometric signature examination as a separate field combining analysis of the writing with analysis of the recorded data. [3]
Provide the name of the system or institution where the signature was made and the format of the available file. You do not need to install software or export further versions yourself. How the material will be shared is determined after its type has been identified.
What to agree before handing over a document
Agree on a list of items to be handed over, how receipt will be confirmed and how originals will be returned. Keep them in their existing condition; do not add writing next to the signature. In your first message, include a description of the available material, questions and any relevant deadline. Get in touch about an initial assessment of a document.
Sources
- ENFSI, Best Practice Manual for the Forensic Handwriting Examination, 4th edition, 2022, annex 3, section 9.3; annex 4, section 4.2.4.
- NISTIR 8282R1, Forensic Handwriting Examination and Human Factors, 2021, chapter 1.2.7.
- Institute of Forensic Research, Handwriting and Document Examination Laboratory, the scope of biometric signature examinations.
Sources accessed: 23 October 2026.