Mumbai, Nov. 16: A defence witness in the Pramod Mahajan murder case today showed a sessions court how an SMS can be tampered with using specialised software.

The demonstration was to prove a claim by the lawyers of Praveen Mahajan — the late BJP leader’s brother and prime accused — that a threat message allegedly sent by their client to Pramod had been fabricated or doctored.

The defence witness, software engineer P. Harikrishnan, began his demonstration seated next to additional sessions judge S.P. Daware in his chamber. Special public prosecutor Niteen Pradhan and defence counsel Mukesh Modi sat behind the engineer.

Harikrishnan accessed the memory of the Moto Razr phone — the same model Pramod used before his death — on a laptop using Microsoft Visual Studio software. He then opened and modified a text message. However, he failed to transfer it back to the cellphone.

The defence then asked the judge to allow another demonstration. Daware allowed it, but warned Harikrishnan that this would be his last chance.

The second demonstration got under way after lunch. The phone inbox had 29 messages, which were shown to the prosecution. Pradhan chose message No. 18 that read: “People say that good friends are hard to find, did you know why? That’s because the BeSt like U are already MINE.” The prosecution asked the engineer to replace “the BeSt like U are already MINE” with “Who says that you are known by thy company?”

Harikrishnan said the sentence was too long and he could only fit in till “thy”. The modified message was then transferred back to the cellphone.

Pradhan then cross-examined Harikrishnan, and the engineer said the software he had used was “freely available in the open market”.

The court said the cross-examination would be continued on Monday.

After the hearing, Pradhan told The Telegraph: “There are two important things that came out clearly during the demonstration. First, Harikrishnan said only a text message existing in the mobile phone inbox could be modified. You cannot insert a whole new text message into the phone.”

The prosecutor said the demonstration also revealed that the characters or bytes of the modified message should be the same as the original. “If the message is “I love you”, containing 10 characters, then it could be modified as “I kill you”, which has exactly the same number of characters.”

Pradhan pointed out that Praveen had claimed he never sent the threat SMS, but Reliance Infocomm, the mobile phone operator, had certified that it was sent from his phone. “If he did not send the message and if a text message cannot be inserted into a phone, then where has the text message come from?” he asked.