It is a matter of trial.
Section 47 reads as follows: When the Court has to form an opinion as to the person by whom any document was written or signed, the opinion of any person acquainted with the handwriting of the person by whom it is supposed to be written or signed that it was or was not written or signed by that person, is a relevant question
Handwriting Expert's Opinion Not The Only Mode To Prove Signature And Handwriting : Supreme Court We think it would be extremely hazardous to condemn the appellant merely on the strength of opinion evidence of a handwriting expert. It is now well settled that expert opinion must always be received with great caution and perhaps none so with more caution than the opinion of a handwriting expert. There is a profusion of precedential authority which holds that it is unsafe to base a conviction solely on expert opinion without substantial corroboration. This rule has been universally acted upon and it has almost become a rule of law. It was held by this Court in Ram Chandra v. State of U.P. AIR 1957 SC 381 that it is unsafe to treat expert handwriting opinion as sufficient basis for conviction, but it may be relied upon when supported by other items of internal and external evidence. This Court again pointed out in Ishwari Prasad Misra v. Mohd. Isa AIR 1963 SC 1728 that expert evidence of handwriting can never be conclusive because it is, after all, opinion evidence, and this view was reiterated in Shashi Kumar Banerjee v. Subodh Kumar Banerjee AIR 1964 SC 529 where it was pointed out by this Court that expert’s evidence as to handwriting being opinion evidence can rarely, if ever, take the place of substantive evidence and before acting on such evidence, it would be desirable to consider whether it is corroborated either by clear direct evidence or by circumstantial evidence. This Court had again occasion to consider the evidentiary value of expert opinion in regard to handwriting in Fakhruddin v. State of M.P. AIR 1967 SC 1326 and it uttered a note of caution pointing out that it would be risky to found a conviction solely on the evidence of a handwriting expert and before acting upon such evidence, the court must always try to see whether it is corroborated by other evidence, direct or circumstantial.”
The approach of a court while dealing with the opinion of a handwriting expert should be to proceed cautiously, probe the reasons for the opinion, consider all other relevant evidence and decide finally to accept or reject it.”
Therefore you wait for the trial court to conduct the proceedings as per law and then decide about what next