The police, which heaved a sigh of relief over the court order giving death penalty to the four convicts, said it will incorporate the "lessons" learnt from the case in the training module for its personnel for use in other cases.
"This verdict has done two things, number one, it has sent a message of deterrence to the criminals and number two, it has also sent a message of greater belief for the common man in the whole criminal justice system," said Joint Commissioner of police (South-Western) Tajender Singh Luthra.
Talking about the "meticulous scientific investigation" of the case despite being under tremendous pressure from all quarters, Vivek Gogia, Joint Commissioner (South-Eastern) who closely monitored and supervised the investigations of the case, said the judgement is a "lesson" and the force will incorporate the points praised by court in its probe in its training modules.
"We gathered DNA samples from nail scrapping and developed dental marks from the bite marks. I think it is the first case in which Odontological forensics -a way of identifying people by their teeth -- was used.
"We had sent the samples to an expert in Dharwad, Karnataka from where we got positive finding which was produced before the court as evidence," he said.
"We consider this judgement as a lesson. The points which have been appreciated and accepted by the court we will incorporate them in our training modules and try to repeat it. Although different cases have different dimensions, but still, we will try to implement the new techniques," said Gogia.
He said, "The most important point for us today is to continue it further both in security and for successful prosecution so that it can act as a deterrent."
Amid nationwide outrage and massive protests in the aftermath of the gang rape with even Delhi Chief Minister Sheila Dikshit joining the anti-police chorus, a dedicated team nabbed the culprits, collected scientific evidence and put together a charge sheet within a record 17 days.
"Filing of the charge sheet was a very important step. Normally, we have 90 days' time to file a charge sheet in such cases, but here we felt our moral as well as legal duty to put forward the evidence before the court as soon as possible.
"Within 17 days, we produced a complete charge sheet before the court and I can say my team worked day in and day out in this case," said Gogia.
On December 17, Delhi police identified bus driver Ram Singh, his brother Mukesh, Vinay Sharma and Pawan Gupta as the suspects in the case, they were arrested the next day while the delinquent juvenile was nabbed from Anand Vihar bus terminal on December 21.
The sixth accused, Akshay Thakur, was apprehended from Aurangabad district of Bihar on the intervening night of December 21-22.
But the biggest challenge before the police was to collect scientific evidence, mainly because the bus in which the girl was brutalised and her friend beaten up was washed by the accused and their clothes were burnt.
But the police collected burnt pieces of cloths, blood and other DNA samples and matched bite marks on the bodies of the accused with the teeth of the girl and vice versa to nail the culprits in the case.
"During the first 48 hours of the case, our primary concern was to prevent loss of evidence. In any case, the first challenge is to identify the right accused and the right crime scene. When we saw the crime scene (the bus) first, it was washed and we were worried whether we would be able to pick sufficient evidence from it.
"But the persistence of our team paid off when we removed the aluminium floor of the bus and got blood and other DNA samples beneath it. So when we got corroborative evidence, we can produce comprehensive proof before the court," said Gogia.
Recalling the entire investigation, a senior police official, who was part of the core investigating team, says that none of them slept for several days at stretch.
"We were working tirelessly at the Vasant Vihar police station. The biggest challenge was to avoid the various pressures and concentrate on the job. Coordinate with various agencies such as the Central Forensic Science Laboratory for test results and the home ministry to get evidence from the Singapore hospital," he said.
He said after filing the charge sheet on January 3, they were confident of proving the case. "Even if all the 85 prosecution witnesses had turned hostile, the scientific evidence were so strong that the case would have sailed through," he said.
Gogia the lessons learnt regarding sensitisation and training in this case, will be accommodated."We have already taken the first step. During a lecture series for the senior officials I have shared all these points with them. We are also giving a detailed report of the case to the training department so that it can be shared further," he said.
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