A magistrate who conducted an inquest has ordered police to investigate the death of Tharoor's wife, Sunanda Pushkar. She died on Friday just days after she accessed his Twitter account to accuse him of adultery with a Pakistani journalist and getting into a public spat with the woman.
An autopsy has found that Pushkar likely died of an overdose of anti-depressant drugs.
Tharoor, who was once a candidate for UN secretary general, has asked authorities to speedily conclude investigations, saying he was "horrified" by media speculation about him and his wife.
The widely published photographs of a distraught Tharoor after his wife's funeral are in stark contrast to years of media coverage of the well-dressed, former high-flying diplomat who has been courted from India's cocktail party circuit to US television chat shows.
A prolific author and one of India's first major tweeting politicians, the US-educated lawmaker and the beautiful Kashmiri who became his third wife were regulars in the social pages. But Tharoor has also been immersed in a corruption scandal and Twitter controversies have dogged him for years.
Media accounts of Pushkar's last days, spiced by the involvement of a journalist from the country's old foe, Pakistan, have gripped the country over the past week.
The tale of one of the wealthiest figures in government has coincided with the growing prominence of politicians who have emphasized their less-privileged roots.
Anti-corruption leader Arvind Kejriwal, a former tax civil servant who leads the Common Man's Party and eschews VIP privileges like official cars, and Hindu nationalist Narendra Modi, touting himself as the son of a tea stall owner, are now dominating as a general election approaches.
"This is the era of the rise of the common man, the tea seller," said Sagarika Ghose, deputy editor of CNN-IBN and a leading political commentator. "There is a sense that Tharoor is not what India is about these days.
"There is a feeling that the elites are getting their comeuppance, that their time has gone."