Shashi Tharoor has till now been questioned thrice in the case. (File photo)
Congress MP Shashi Tharoor might have to take a lie-detector test in the murder case of his wife Sunanda Pushkar.
Investigators are soon likely to ask for the court's permission to conduct a lie-detector or polygraph test on Mr Tharoor as they are trying to take the high-profile case to a logical conclusion, said sources in the Delhi Police.
The investigators have so far conducted polygraph tests on six people, all prime witnesses in the case, including Tharoors' domestic help Narayan Singh, driver Bajrangi and Sanjay Dewan, a close friend of the couple.
Mr Tharoor was not subjected to the test but was questioned thrice in the case. 52-year-old Ms Pushkar was found dead in a five-star hotel suite on January 17 last year, a day after she was involved in a spat with Pakistani journalist Mehr Tarar on Twitter over the latter's alleged affair with Mr Tharoor.
The sources said Mr Tharoor is likely to be questioned again as the eight-page Federal Bureau of Investigation or FBI report of Ms Pushkar's viscera brought to fore certain details crucial to the probe. The police will soon submit the report to court.
The report received via e-mail on Tuesday, suggested that Ms Pushkar died of some poison, which they have named, said sources. However, police have so far refused to disclose the type of poison mentioned in the report.
Delhi Police Commissioner BS Bassi said the report from the Washington DC-based laboratory of FBI would soon be handed over to a medical board for examination.
"The FBI lab had conducted analysis of various substances. And this should give an indication (as to the reason behind her death) once the doctors go through the report," said Mr Bassi.
The report has ruled out the theory of the variant of a radioactive element named Polonium having caused Ms Pushkar's death, Mr Bassi said, adding that radiation levels in her viscera samples were "within the standard safety norms".
Analysis of the report shall take time and, even after submission in court, it shall only be shared once all the legal issues connected with it have been studied, he said.