Court should not avoid recourse to Section 73 of the 1872 Act by holding that the Court is not an expert.
“12. The argument that the Court should not venture to compare writings itself, as it would thereby assume to itself the role of an expert is entirely without force. Section 73 of the evidence Act expressly enables the Court to compare disputed writings with admitted or proved writings to ascertain whether a writing is that of the person by whom it purports to have been written. If it is hazardous to do so, as sometimes said, we are afraid it is one of the hazards to which judge and litigant must expose themselves whenever it becomes necessary. There may be cases where both sides call experts and the voices of science are heard. There may be cases where neither side calls an expert, being ill able to afford him. In all such cases, it becomes the plain duty of the Court to compare the writings and come to its own conclusion. The duty cannot be avoided by recourse to the statement that the court is no expert. Where there are expert opinions, they will aid the Court. Where there is none, the Court will have to seek guidance from some authoritative textbook and the Court's own experience and knowledge. But discharge it must, its plain duty, with or without expert, with or without other evidence. We may mention that Shashi Kumar v. Subodh Kumar and Fakhruddin v. State of Madhya Pradesh were cases where the Court itself compared the writings.”
Murari Lal v. State of Madhya Pradesh (1980) 1 SCC 704