Were Dr Rajesh and Nupur Talwar on the internet on the night when their daughter Aarushi and servant Hemraj were murdered in the family's' flat?
The Talwars have consistently claimed they were alseep in their air-conditioned room, unaware of the gruesome events taking place in their home on the night of 15-16 May 2008. But in the popular mind, there has always been scepticism about this.
As in so many other aspects of this case, the scepticism has its roots in the stories the CBI circulated to a legion of stenographer-journalists who faithfully reported them.
In 2010, when the CBI filed its closure report, the stories were quietly 'withdrawn'. A.G.L. Kaul concluded that evidence gathered on the internet activity on the night of the murders was "unreliable".
This "unreliable" evidence was, nevertheless, made a part of the case against the Talwars, defence counsel Tanveer Ahmed Mir pointed out to the trial court in Ghaziabad on Friday.
As a proposition, the circumstance that the Talwars' router appeared to switch on and off through the night is compelling. It paints a chilling picture: the murderers aren't asleep at all, they are collected and cold-blooded enough to surf the internet.
But what about the evidence? That is where the story breaks down. Why did Kaul find the evidence unreliable in the first place? Because an almost identical pattern was evident from the logs of the day after the murders.
This defied explanation, because on the next day, the Talwars' place was crawling with police and visitors. The modem, in Aarushi's blood-covered room, lay untouched.
Fact is, there is a perfectly reasonable explanation for a modem/router switching on and off without someone physically doing this.
In fact, in the testimony of an expert CBI witness on the subject, it emerged that there were at least eight reasons (including idle time out; lease time expiry, admin reset, lost carrier and so on) for unusual start, stop activity.
These phenomena are common. Most internet users in this country have experienced them.
Was it possible to narrow the cause down to what was actually responsible that night? It was, the expert had told the court. What he would require was three detailed logs: those of the computers in use; logs from the router; and comprehensive logs from the internet service provider.
Scientists of the Computer Emergency Response Team (a central government body) whose expertise the CBI says it used, even wrote to the agency requesting the three logs. They were never provided.
What they got instead, was a partial log from Airtel with three fourths of the information missing. Including a very important column: 'cause of termination' (of each session).
The CERT scientists thus couldnt say anything conclusively. The CBI has never explained why the logs weren't provided. The Talwars' computer was mined and analysed for information of all sorts, including junk mail.
And the router? Well that wasn't ever seized: it remains, to this day, with the Talwars.
Like the scalpel that was never asked for, the CBI didn't bother with the router. Why? Only one reasonable explanation emerges: its record might have blown away the CBI's theory that the Talwars were awake surfing the net having commited two murders.
In the perception stakes it made much more sense to keep the story alive. For the media, its consumers--and the trial court.
The court will resume hearing on Wednesday, when another circumstance the CBI claims points to the guilt of the Talwars will be taken up: the claim that three of its witnesses saw blood-stains, some of them "wiped" on the staircase leading up to the terrace on the morning after the murders.
The insinuation is that this shows how Hemraj's body had been carried to the terrace and concealed by the Talwars in an attempt to make the dead man a suspect. (Hemraj's body was found a day after Aarushi's, once the police got around to breaking the blood-stained lock on the terrace door.)
Of the three witnesses who claim they saw blood was Sanjay Chauhan, a NOIDA sub-divisional magistrate who just happened to drop by at the crime scene on his way back from his morning walk.
The court also heard that he drove 56 km each day in order to get his exercise.
Mir told the court that against the three who had, there were nine prosecution witnesses, including the top policemen at the crime scene, who said they had never seen any blood on the staircase.
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