As protests demanding speedy justice for the RG Kar brutality intensify, with an anguished city switching off lights to hold candlelight vigils and the Supreme Court preparing to hear the case again, there is little clarity on the headway that the CBI has been able to make since it took over the investigation.

The central agency is supposed to inform the apex court about its findings in the rape and murder of a junior doctor at the medical college hospital on August 9. The Telegraph lists some of the questions that the people of this city expect the CBI to answer in the Supreme Court

◉ Was the rape and murder the act of one man or more?

The allegation is that it could not have been a one-man job. However, the Kolkata Police have arrested only one person, a day after the crime. Former RG Kar principal Sandip Ghosh and his three alleged accomplices were arrested on September 2 but on graft charges, not in connection with the rape and murder. People expect clarity from the CBI.

More than one CBI officer told this newspaper that the evidence they had gathered so far suggests the involvement of one man. They also added that the probe was still on. What the CBI tells the court is crucial.

◉ What do the tests on the samples collected tell?

Three sets of tests have been conducted

a) Tests to determine the DNA strain/strains in the samples collected from the body, the accused and the crime scene

b) Forensic analysis of the deceased’s clothes, which could also show if one or more people assaulted her

c) Histopathological tests on the organs that show possible poisoning or drugging and even assault

Forensic experts said in case of a rape, injury marks are found on the victim as well as the accused. The nature and location of the injuries on the victim are often matched with injuries on the accused to figure out their presence in the tussle. Such a tussle usually leaves hair and other signs such as broken nails and thread from broken stitches or buttons and pins. Some such items are also being tested.

The results of at least one set of tests are already available with the CBI, sources said.

CBI sources said the test results received so far did not indicate DNA strands of more than one person. The central agency is awaiting more test results.

Samples sent for tests include a “white thick viscid liquid” that was found inside the genitalia of the 31-year-old junior doctor.

◉ Is the seminar room the crime scene?

Kolkata Police have said so.

One section of the CBI suggested that they were still trying to ascertain whether the crime took place in the exact location where the body was found — the seminar hall on the third floor of RG Kar’s emergency building.

The central agency has visited the seminar room and its adjoining places at least six times. They have done a 3D mapping of the place and taken pictures of neighbouring rooms and the corridor.

They have also tried to find out what was there in the section of the chest medicine department whose demolition was stopped after allegations of evidence tampering.

The CBI has spoken with hospital security guards, the junior doctor’s colleagues who were on duty on August 9, cops known to be close to arrested civic volunteer Sanjay Roy and members of the Kolkata Police special investigation team that was handling the probe before it was handed over to the CBI.

Almost all those interrogated by the CBI were asked about when they reached the crime scene and what they saw. Repeatedly asked questions were aimed at identifying inconsistencies on the place of occurrence (PO) as is being alleged, some of those who faced the interrogators said.

Candles lit at the protest site at RG Kar hospital on Wednesday night. Picture by Sanat Kr Sinha

◉ Was the crime scene tampered with?

Solicitor-general Tushar Mehta, representing the CBI, told the Supreme Court during the last hearing on August 22 that the crime scene was “altered”.

Kapil Sibal, who was representing the Bengal government, denied the allegation, saying the entire investigation by Kolkata Police had been videographed.

The police in Calcutta later said an altered crime scene need not mean a doctored crime scene. They asserted that the scene of the crime had been preserved to ensure there was no tampering of evidence.

Some of the statements from the victim’s parents, however, have stoked further allegations. They said they were made to wait for three hours before they could see their daughter’s body and the police had throughout kept them “under pressure”. They have also suggested a change in the cloth covering their daughter’s body and implied destruction of evidence.

◉ What has the repeated interrogation of the doctors on duty that night, security guards and police posted at the hospital revealed?

According to CBI sources, the doctors said they had no idea who entered the seminar room after they had dinner with the junior doctor in the early hours of August 9 in the seminar room.

CCTV footage collected by the police, now with the CBI, revealed Roy was in the hospital between 3.50am and 4.40am on August 9.

The police have told the CBI investigators that a Bluetooth device seen on Roy when he entered the seminar room was missing when he came out.

Sources in the CBI said statements from Roy’s colleagues revealed the civic volunteer was also in the hospital earlier on the evening of August 8.

◉ Is the corruption at RG Kar linked to the crime?

A section of the protesting junior doctors have alleged so.

A separate team of officers from the CBI’s anti-corruption branch has started a probe into the alleged financial irregularities and Ghosh, on whose watch the heinous crime took place, has been arrested along with three alleged accomplices.

The CBI has yet to clarify if the two crimes are linked.

◉ What have the polygraph tests on Ghosh and the others shown?

The CBI has conducted polygraph tests on at least 10 persons, including Ghosh, Roy, an assistant sub-inspector of police known to be close to Roy, four junior doctors and a civic volunteer.

Sources in the CBI did not want to reveal the outcome of the tests.

◉ Is the CBI happy with the chronology of events?

The CBI sources said the hospital told Kolkata Police they came to know about the death of the junior doctor at 9.45am on August 9. Senior investigating officers of Kolkata Police said they received the first intimation around 10.10am. It took a few minutes for the police personnel to reach the crime scene from the on-campus outpost.

The CBI wants to find out more about the 25-minute gap.