Shashi Tharoor's wife Sunanda Pushkar was found dead at the luxurious Leela Hotel in Delhi in January 2014.
Congress lawmaker Shashi Tharoor may be asked to undergo a lie detector test in the murder case of his wife Sunanda Pushkar, sources told NDTV. Six others have already undergone the test and Mr Tharoor is the only one left, they said.
The possibility of Mr Tharoor being tested came up after the US Federal Bureau of Investigation sent a report to the Delhi Police, ruling out the role of Polonium or any other radioactive substance in Ms Pushkar's death two years ago.
The police, however, expect that an analysis by the FBI in the eight-page report could finally help find how Ms Pushkar died, sources said. "We are still to examine the report," said Delhi Police chief BS Bassi.
Polygraph tests -- the results of which are inadmissible in a court of law -- have been also conducted on six people: Narain Singh, Mr Tharoor's domestic help, driver Bajrangi and family friend Sanjay Dewan, all listed as prime witnesses.
Mr Bassi told NDTV that a decision on whether to call Mr Tharoor - who has already been questioned multiple times -- again for questioning will be taken after the medical board involved in the investigation into the case gives its opinion.
But the police will need a court permission conduct the test on Mr Tharoor. A polygraph test can be held only with the permission of the court and the agreement of Mr Tharoor.
Ms Pushkar, 51, was found dead at the luxurious Leela Hotel in Delhi in January 2014. For a year, her death was considered a case of suicide, but earlier this year the Delhi Police claimed she had been poisoned and registered a murder case. No one has been named as a suspect in the case so far.
In February, Ms Pushkar's viscera samples were sent to the FBI lab in Washington in February after a panel of doctors from Delhi's All India Institute of Medical Sciences concluded that the poison could not be detected in Indian labs.
For a time, it was suspected that the poison was Polonium, but the FBI has ruled out that or any other radioactive substance.