The CBI has sought details of some of the post-mortems conducted at RG Kar Medical College and Hospital before and after the autopsy of the junior doctor who was raped and killed at the hospital on August 9.

“We want to know the details of the procedures usually followed while performing a post-mortem at the hospital. This will help us better understand the procedures that were followed while conducting the autopsy of the doctor (the rape and murder victim),” a senior CBI officer said.

The central agency, which took over the investigation of the rape and murder following a Calcutta High Court order, has sought from the hospital details of the procedures that a doctor of forensic medicine follows while conducting the post-mortem of a person found dead under unnatural circumstances, CBI sources said.

A team of three doctors, two from RG Kar and one from NRS Medical College and Hospital, had carried out the post-mortem of the junior doctor.

The team was headed by Apurba Biswas, a professor in the department of forensic medicine and toxicology atRG Kar.

There were allegations that the process was hurried.

Sources in the CBI said the reply from the RG Kar authorities would help the investigators identify if there were any procedural lapses and understand the standard practice for conducting a post-mortem.

Several senior doctors performing post-mortems at state-run medical colleges in Calcutta said the process involves several steps and could be broadly divided into two categories — external and internal examination.

The injuries on the body are noted down during the external examination with references to the type of injuries and other details.

During the internal examination, various types of incisions are made — y-type, u-shaped, vertical and semi-circular — to reach the organs and detect their condition and abnormalities.

“The internal examination is time-consuming, lasting several hours. Samples like tissues are collected during the internal examination for laboratory investigations,” said a senior doctor at Medical College Kolkata.

“The findings are noted down in the form of a report and the results of the lab tests are later appended to it.”

Senior RG Kar officials refused to speak about the CBI’s queries.

“All we can say is that the CBI wants to find out how a post-mortem is conducted at the mortuary of the medical college and how medico-legal reports are drawn up,” said Saptarshi Chatterjee, the superintendent and vice-principal of RG Kar Medical College and Hospital.

The post-mortem report of the junior doctor, sourcessaid, mentions multiple bruises and “hemorrhagic spotson the inner side of herepiglottis”.

The epiglottis is a cartilaginous lid that prevents food and water from entering the windpipe and the lungs when a person swallows.

Before submitting its first chargesheet in the case of rape and murder of the junior doctor, the CBI questioned all the members of the team that performed the post-mortem of the postgraduate trainee.

According to the chargesheet, the victim “died 12 to 18 hours” before the autopsy and that it was conducted “under videography” between “18.10 hours to 19.10 hours” onAugust 9.