From the forensic point of view it is not easy to identify a person as an author of writing in graffiti mode, but at least in some cases it seems to be possible.
Brandner, W. (2017). Possibilities to compare graffiti with handwriting. Nowa Kodyfikacja Prawa Karnego, 45, 101–107. https://doi.org/10.19195/2084-5065.45.9