João Hugo Eduardo de Sequeira (20 April 1915 – 19 February 1989), popularly known as Dr. Jack de Sequeira,[1] also known as Jak Siker according to local naming conventions, was an Indian politician, businessman and former medical practitioner who is widely considered in Goa to be the "Father of the Opinion Poll", which led to the former territory attaining statehood in 1987.

Born to Goan emigrant parents in British Burma (now Myanmar), de Sequeira shaped politics in Goa during the 1960s and 1970s in particular.

After completing schooling in Portuguese medium at the Lyceum, he studied medicine at Escola Médica de Goa.

[5] He played a pivotal role in convincing the government of India to hold an opinion poll to decide the issue of the merger of Goa into the state of Maharashtra.

The MGP and politicians in Maharashtra were elated at the victory and touted it as a mandate that the majority of Goans were in favour of merger.

De Sequeira visited New Delhi along with his MLAs and impressed Nehru about the need of an opinion poll on this matter.

However Nehru died before Parliament could take this decision and Lal Bahadur Shastri succeeded him as Prime Minister.

A delegation consisting of MGP MLAs and Maharashtra’s leaders went to New Delhi to convince him that a vote on the merger should be conducted in the Goa Assembly.

They opposed the move to get the merger voted in the Assembly and impressed on Shastri and Kamraj, the need to put this question before the people of Goa themselves.

[10] He impressed them that if Maharashtra managed to convince the centre to merge Goa into Maharashra, it would only bolster their case for Karwar and Supa.

[12] Now that the referendum would be conducted, de Sequeira feared that Bandodkar may use the state’s administrative and law-enforcement machinery to browbeat the anti-mergerists into submission.

[18] In his analysis of the 1963 Goa elections, Ram Joshi argues that the urban Hindu elite, perhaps more ambitious politically, was more inclined to vote for a party which stood for separate statehood.