Why a bank's handwriting expert couldn't prove forgery

A bank brought in a handwriting expert to prove a signature was fake. The judge said: not enough.

The expert had measured the slopes, the loops, the pressure points. He was certain it was a forgery. Punjab National Bank was certain too. But the court looked at the same evidence and reached a different conclusion — not about the signature, but about the law. Could a bank win a civil case on the word of a handwriting expert alone? The judgment in Punjab National Bank Ltd. v. Mercantile Bank of India Ltd. answered that question with a single, firm word: no.

When the expert walked into court

Neither side had a witness who had actually seen the signature being made. No confession. What Punjab National Bank had was an expert — a man trained in handwriting comparison — who was prepared to testify that the signature was a fake. He walked into court with his magnifying glass and his charts. The charts were covered in enlarged loops and slants, each stroke marked with a red pen to show where the pen had paused. He pointed to the tremors in the strokes, the tiny quivers that suggested hesitation. He showed where the pen had hesitated, the ink pooling slightly at one curve. He explained why the slant was wrong and the spacing inconsistent. To the layperson, his testimony sounded definitive. The courtroom fell silent as he traced a trembling finger along the disputed line. But the court was not a layperson.

The dispute was about money. Punjab National Bank had paid out on a document. Mercantile Bank of India said the signature authorising that payment was not genuine. The case turned on a single piece of paper — a signature that one side insisted was real and the other side insisted was forged. The file on the judge's desk contained only the expert's report and the two sets of signatures. The smell of old paper rose from the file as the judge turned each page slowly, comparing the loops and strokes with his own eyes. The expert sat in the witness box, his charts spread before him, waiting. But the law did not ask the judge to decide whose eyes were sharper. It asked whether the expert's opinion could stand alone.

What Section 47 actually demands

The law on handwriting evidence in India sits inside Section 47 of the Evidence Act, 1872 (the rule that allows a person familiar with someone's writing to give an opinion on whether a disputed signature is genuine). The section says that a witness can give an opinion on handwriting only if that witness is "acquainted" with the handwriting in one of the ways the law recognises — having seen the person write, having received documents purporting to be in that person's handwriting, or having dealt with that person's writing in the ordinary course of business.

The bank's expert was not acquainted with the signatory's handwriting in any of these ways. He was a stranger to the writing until the case landed on his desk. He had studied the signature for the first time when the bank handed him the disputed document and a set of admitted signatures for comparison. That, the court said, was not enough. The expert's opinion was admissible only if the condition in Section 47 was first satisfied — that the witness had the kind of familiarity with the handwriting that comes from prior exposure, not from post-dispute analysis. The expert failed that test. The court observed that the opinion of an expert in handwriting is admissible only if the condition laid down in Section 47 — that the witness is established to have been acquainted with the writing — is fulfilled.

This condition is not a technicality. It is a gatekeeping rule designed to ensure that the witness giving the opinion has a baseline of knowledge about the handwriting in question. A person who has never seen the signatory write, who has never received a letter from that person, who has no prior experience of that person's hand — that person is not in a position to say whether a disputed signature is genuine or forged. The expert may be a skilled handwriting analyst in general, but general skill is not the same as specific familiarity. The law demands the latter before it will even consider the former.

Why the court refused to rely on the expert alone

But even if the expert had passed the Section 47 test, the court made clear that his opinion would not have been enough. The judgment established a broader principle: expert opinion on handwriting is inherently fallible, and a court should not base its decision on such opinion unless it is supported by other evidence. The Court observed that because human judgment is fallible, placing sole reliance on expert handwriting analysis can be hazardous, and the approach should be one of caution.

The reasoning was straightforward. Handwriting comparison is not a science with fixed, measurable outcomes. Two experts can look at the same signature and reach opposite conclusions. The same person's handwriting can vary with mood, health, age, and the surface they are writing on. A forger can become skilled at copying signatures. The court held that placing sole reliance on a handwriting expert's opinion is hazardous. The word "hazardous" is significant — it suggests not just that the evidence is weak, but that relying on it alone creates a real risk of error. The court was not saying that experts are dishonest. It was saying that experts are human, and human judgment, even when trained, can be wrong.

The court's language was careful. It did not say that handwriting experts are useless. It said that their opinions must be "approached with great care and caution." The phrase appears twice in the judgment — once in connection with the admissibility condition under Section 47, and once in connection with the broader principle of corroboration. The repetition is deliberate. The court wanted to make clear that caution is required at every stage: when deciding whether the expert is qualified to give an opinion, and when deciding how much weight to give that opinion. Each stage demands a separate inquiry, and each inquiry demands a rigorous approach.

The corroboration requirement

The ratio (the court's central reasoning) was this: the opinion of a handwriting expert should not be relied upon unless it is corroborated by other evidence. Corroboration means independent evidence that points in the same direction — a witness who saw the document being signed, a business record that shows the transaction was authorised, a letter from the signatory acknowledging the document, or any other piece of evidence that supports the expert's conclusion. The court's language was clear: "the opinion of a handwriting expert should not be relied upon unless it is corroborated by other evidence."

This requirement of corroboration does not come from the text of Section 47 itself. The section does not say "expert opinion plus something else." The court read that requirement into the law as a matter of prudence — a safeguard against the risk of wrongful conclusions based on fallible human analysis. The effect is significant. In any civil case where the disputed fact is a signature, the party relying on the forgery cannot simply hire an expert and rest its case. If no corroborating evidence exists, the expert's opinion, no matter how confident, will not be enough.

The court's approach reflects a deeper truth about evidence law. The purpose of a trial is not to find the most confident witness. It is to assemble a body of evidence that, taken together, points reliably to a conclusion. A single expert's opinion, however well-presented, is a single data point. The law demands more. It demands that the data point be confirmed by other data points — that the expert's conclusion be tested against the facts of the case, not accepted on the expert's say-so alone.

What this means for banks and businesses

For banks, this judgment has practical teeth. A bank that suspects a forged signature on a cheque, a loan document, or an authorisation letter cannot treat a handwriting expert's report as the end of the investigation. The bank must look for other evidence — the circumstances in which the document was created, the behaviour of the parties, the timing of the transaction, the presence or absence of witnesses, the consistency of the signatory's conduct. For businesses, the same principle applies. A company that disputes a contract on the ground that the signature is forged must build a case that goes beyond the expert's report.

The practical lesson is straightforward. Before filing a case, a party should ask: what corroborating evidence exists? If the answer is "none," the case may be too weak to file — not because the signature is genuine, but because the law will not allow a single expert's opinion to carry the entire burden of proof. The party must either find corroborating evidence or accept that the case cannot be won. This is not a flaw in the law. It is a safeguard against the risk of wrongful conclusions — the risk that a confident expert, armed with charts and a magnifying glass, might persuade a court to accept a conclusion that the evidence does not support.

THE PLAY: Never file a civil case based solely on a handwriting expert's opinion — the court will require corroboration, and without it, the expert's testimony becomes a liability, not an asset.

The signature that could not speak

Punjab National Bank brought an expert. The expert brought his charts and his certainty. But the signature on that piece of paper remained silent, and the court refused to let one man's eyes decide what the law required a body of evidence to prove. The expert packed up his charts and left the courtroom. The file on the judge's desk was closed. The signature stayed where it had always been — on the paper, unresolved, a silent question that the law would not answer with a single voice.