Dialectology, the authentication of art works, is that part of forensic linguistics we use the most in our field. What this means is that we analyze language to determine if it was written by a native speaker of the language.
An example is the drawing below supposedly executed and inscribed by Salvador Dali.
The line of text at the bottom reads, "Por la grazia de dios." "Grazia", is Italian. The Spanish spelling is Gracia. No native Spanish speaker would ever make such an error. Not only because it looks different, but also because in Spain the letter Z is pronounced a bit like an English "th". The result is that to a native Spaniard like Salvador Dali, Gracia sounds completely different from Grazia.
Salvador Dali was an educated man. He wrote several books. He would never have misspelled such a word.
Another example of using forensic linguistics to evaluate a document or an inscription is this certificate which was presented in support of a painting attributed to Pablo Picasso.
Although the "expert" is apparently based in London (without address), he had his attribution professionally translated, apparently by a professor no less. From a linguistic standpoint, problems appear immediately, such as with the very bizarre and nonsensical title of the document, "Declaration of examination effect," and they continue through the entire document.
In spite of the five stamps, two signatures, and two Professor titles, the document is obviously a bogus creation.
We apply forensic linguistics to writings, documents, and inscriptions in many languages in the course of authentication paintings. It is one of the many forensic methods we use.
If you have a painting, a drawing, or some other work of art that needs to be authenticated, please contact us at email@example.com or 212-203-7833 and we will help you.