Several new forensic techniques are being used in the Shakti Mill gangrape case to extract as much evidence against the accused as possible.
While crime scene foraging — a technique normally reserved for terror cases — was carried out by a team of the Central Forensic Science Laboratory (CFSL), the agency that worked on the Delhi gangrape case as well, at the Shakti Mill compound on Tuesday; the police revealed they are using the Layered Voice Analysis (LVA) test — never employed by the Mumbai police — on the five accused.
Joint commissioner of police, crime, Himanshu Roy said, “The LVA technique would be used for the first time. Though it is not admissible as evidence in a court, it is a potent investigation tool.”
Explaining the procedure, an officer said they would record the voice of the accused while asking them general questions, which are followed by questions related to the crime. “The deviation in the two tones gives us an entry point for questioning.”
Former Maharashtra FSL director and present chairman Helik advisory R Krishnamurthy explained how the LVA works.
“One can detect deception by identifying the stress and emotional status in a recorded conversation. This technique can detect the intention behind the lie and does not require the person’s consent.”
Two psychologists from Ahmedabad FSL, the only government laboratory to have this facility, reached Mumbai to employ this technique.
“Since the accused are habitual criminals, they might try to mislead us. This technique will help us know when they are misleading us,” said the officer. Meanwhile, eight officials of Delhi-based CFSL collected samples from the crime scene for around two hours on Tuesday.