The objective of the expert consultancy is to attribute the authorship of a written text to an alleged author (authenticity and autography of signatures, private writings, wills, etc.). In order to achieve this goal, it uses a methodology that, starting from a preliminary physical analysis of the document and the handwriting, and passing through graphological analysis, leads the expert to a conclusion about the authenticity of the written text that varies in a range between certainty and impossibility.

In order to do this, the graphologist uses comparative scripts, which must be produced by the parties to a sufficient extent to allow them to collect a quantitatively and qualitatively adequate sample of graphological signs identifying the graphic style of the author. Comparative handwritings must be homogeneous, i. e. they must be drawn in periods that are as contemporary as possible and in physical conditions (writing support, writing tool) similar to the writing being verified.