Most document cases for handwriting experts in private practice involve handwriting comparisons. How is hand writing differentiated between people? Initially, writers learn to write by emulating a handwriting system taught in school. As students mature, they quickly stray from the copybook forms to making letters with individualizing features. These characteristics may include variations in the form of the writing slant, the spacing between letters, the design and length of approach and termination strokes, the positioning of ‘i-dots’ and ‘t-crossings’, height relationships, the design of numerals, and so forth.
Writer’s need to balance their writing product by the limitations of their writing skill, how elaborate or embellished they wish writing to exhibit and the utilitarian influence of how quickly they would like to write. A person struggling to embellish their writing will require more time than a skilled writer using a plain cursive style.
There is natural variation in the signatures and writing of all people. A document examiner will ask for several known writing samples of a suspected writer for the handwriting comparison. By having several specimens, the signature expert will be able to establish a master pattern or consistency of the writer. The questioned signature will then either conform to the known writing specimens or not.
Handwriting comparisons is a complex process. For example, some signatures may pictorially appear to the be the product of the same person. However, a comparison by a document examiner may prove a signature in question was not genuine but rather the result of a simulation, tracing, or a ‘cut and paste’ fabrication.
It is common to hear a client state they compared a signature in question with one or two known signatures of the purported writer. As a support to their contention a signature was forged, they will note difference during their quick assessment. However, a proper handwriting comparison may show the differences were simply the result of natural variation by that writer. Signature examinations require several known specimens to learn what features are in common from signature to signature and which features vary.