It is impossible for a criminal to act, especially considering the intensity of a crime, without leaving traces of this presence, said the great pioneer of forensic science, Edmond Locard.
The Frenchman’s well-known hypothesis, the ‘exchange principle’ — when two things come into contact there will be some exchange — was used by the Kukatpally police to crack a murder mystery recently.
When 27-year-old Phanishwar (name changed) murdered a woman eight months ago in her house at Kukatpally after having had sexual intercourse with her, he apparently believed he was not leaving an iota of evidence behind.
Found murdered
A resident of Gayatrinagar in Kukatpally, the victim was working in a book binding factory and was found murdered in the house when her husband, also a private company worker, returned home from work on that fateful day in November.
Attempt to mislead
The accused had tied the right leg and arm, and the other two limbs with a piece of cloth each, trying to suggest that she was sexually assaulted by some persons. For first few hours, the police also believed it.
“Surprisingly, there were no injuries on her body. If it was a rape, the woman would have resisted but no such signs were present,” recall investigators.
Were the killers known to the victim? To this end, police picked up nearly 20 persons, including the victim’s colleagues and relatives, and questioned them, but with little success.
The breakthrough came when one of the victim’s co-workers told police that their ex-colleague Phanishwar used to meet the woman every now and then, even though he had already quit their factory.
Investigators detained him, only to stumble upon even more interesting leads: call data records from Phanishwar’s mobile phone.
These indicated that he was in the vicinity of the victim’s locality on the day of the murder.
“Sir, I live in Nalgonda and had brought my wife to the city for medical treatment,” he claimed. Inquiries proved that he was in the city that along with his wife.
DNA evidence
Meanwhile, physical evidence — the victim’s innerwear with semen stains — was sent to the forensic science laboratory for DNA profiling.
Blood samples of all the 20 suspects questioned, were collected and their DNA profiles prepared.
Phanishwar had no defence when his DNA profile matched with that of the semen sample collected from the crime scene.
He eventually confessed to have eliminated the woman with whom he claimed to have developed an illicit relationship while they were co-workers.
Phanishwar maintained that he had lent her nearly a total of Rs. 65,000.
According to his confessional statement, he went to her house on the day of the murder and they engaged in coitus.
The duo later had an argument over the issue of the money he had lent her, culminating in Phanishwar strangling the woman to death with a cooler wire, Kukatpally police said.
