Tampered evidence, delayed lab reports: Why forensics isn’t leading to convictions in rape cases

Forensic investigation should ideally provide clinching evidence in rape cases. Then why are conviction rates so low?

This article is part of a special series: Safety of women in Indian cities

Every time a gruesome rape incident shakes the foundations of our belief in humanity, a few standard arguments make an appearance. Maybe I am being cynical, but my take is that the comments that follow a headline-grabbing rape seem like the script of a 70’s Hindi movie – standard, repetitive, predictable and, at the risk of sounding extremely insensitive, almost entertaining.

“Make every rape punishable by capital punishment.”

“We cannot ask the state to commit murder. It is barbaric and a violation of human rights.”

“Justice delayed is justice denied.”

“We need speedy trials and fast track courts.”

Here we address the last point, because the demand for fast track courts and speedy justice won’t make any sense if the investigation is sub standard. So how do rapes get investigated in our country? Is there a Standard Operating Procedure (SOP) for collecting evidence? Where does it all begin to unravel?

With a conviction rate of about 26 percent, rape and sexual assault cases are among the hardest to prove. It cannot work on the principle of “she said versus he said”. 

I’ll start with how rape is defined. In a nutshell, rape is defined as “…forceful penetration without consent”. To prove this in a court of law, our system largely relies on the testimony of the victim. Forensic evidence is used to support and corroborate her/his statement and help build a water-tight case.

However, collecting forensic evidence is still at a very nascent stage in India. “The problem is the first responder to a crime scene is usually a constable, who really isn’t very well versed in maintaining the sanctity of a crime scene,” says Ashok Gubbi, a city-based lawyer who has worked on cases of rape and sexual assault. “Cross contamination of evidence or a compromised chain of custody means that the evidence becomes inadmissible”.

He gives an example. “The chain of custody is very important for evidence to be permissible in court. There was a case where the forensic lab made a mistake with the nomenclature which identifies the place and the case number. It was human error but that mistake meant all the evidence collected became inadmissible.”

So how does evidence get collected? The first step is the medical examination of the victim in cases of sexual assault. This should be done within 24 hours of the incident by a medical officer in a government hospital. Bodily fluids, residue under fingernails, injuries are all important to establish assault.

One piece of clinching evidence in the Nirbhaya case was the match of the bite marks on the victim’s body with those of the accused. This branch of science is called forensic orthodontology. “To the best of my knowledge, there is only expert in this stream with the Central Forensic Lab at Hyderabad,” says Gubbi.

What is forensic evidence?

Medical reports, post mortem reports (in the event the victim has died), rape kits, crime scene photos, pictures of injuries – all can be classified as forensic evidence. The forensic report, on the other hand, is an analysis of the evidence collected and answers the specific questions asked by the investigating officer.

How many forensic labs are there in India?

There are six central forensic labs that fall under the Ministry of Home Affairs – at Calcutta, Hyderabad, Chandigarh, Guwahati, Pune and Bhopal. The Central Forensic Lab in New Delhi falls under the Central Bureau of Investigation which only handles cases investigated by the CBI. Besides these central labs, every state also has a state forensic lab.

What are the parameters to submit forensic evidence court?

There are three criteria that have to be fulfilled to submit forensic evidence.

  • Established chain of custody
  • Purity of forensic sample
  • Non-tampering of sample

N Yathish, Director, Karnataka State Forensic Lab laid out the challenges they face. “The victim sometimes becomes the problem. They may have a bath or change their clothes etc which means we lose physical evidence.”

After the Delhi Nirbhaya case, serious efforts were made to standardise the way samples were collected. “But we hear of many instances of the three-finger test still being conducted,” says Rashmita Jena, a Supreme Court lawyer who also works in the area of gender sensitisation for the police. “There are also times when the victim has no access to government hospitals nearby, which was also challenged. But that law continues to be there”.

All the evidence collected is then sent to the State FSL with a list of questions given by the investigating officer. “The investigating officer sends us specific questions about the evidence collected, and we try and see if our analysis answers their question,” says Yathish.

Unlike crimes involving firearms where the forensic scientists accompany the investigating officer as a norm, in sexual assault cases, forensic scientists do not automatically become part of the team that collects evidence. “Depending on the gravity of the situation, the investigating officer takes the call of having a forensic expert visit the crime scene,” says Yathish.

Once the collection of evidence is over, the laboratory report can take anywhere between two months to a year! “I have had cases where the DNA report was given after a year” says Gubbi.

Why the delay?

“Quite honestly, the tests themselves take about an hour,” says Rashmita Jena. “The reports get delayed because there are other external pressures. Is the accused influential? The family of the victim gets involved. It creates a lot of chaos.”

Yathish, however says that is no longer the case. “Yes, there was a time when the reports did take a long time,” he admits. “But cases of sexual crimes that fall under the biological crimes section (we have 11 sections at the lab) are taken up on a priority basis. We try and give the report within a couple of months.”

Anupama Killur, who works with Truth Labs, a private enterprise that often collaborates with the state for these analyses, echoes his sentiments. “Murder and rape cases are a priority at the lab,” she says.

So is there personnel crunch? “No, we have been addressing the issue, and the last three months has seen enough recruitment to fill the requirements,” says Yathish.

Gubbi sums it up: “The problem stems from the basics. Constables are often ill equipped to know what kind of questions to ask a rape victim. Sometimes even the officers are at a loss. The cops are expected to don multiple hats – administrator, investigator of finance crimes, local squirms, dog napping and also have the sensitivity of investigating a sexual assault crime. It really is an impossible task.”

Whatever the reasons, there seems to be a crack through which justice slips away for victims of these inhuman crimes. Clearly, asking for fast track courts is counter productive if the process of getting there is flawed.

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