He completed his study of Law from University of Cambridge. and was called at Bar at Lincoln's Inn in 1897. Two years later in 1899, he moved to India and started practice as Advocate at Bombay High Court.
In Burma and British India
In 1916 he served as Secretary to the Burma Legislative Council. He was member of Legislative Assembly of India from years 1921–23. He was the President of Rangoon Municipal Corporation for years 1921–22. Later he served as a member of Indian Tariff Board 1923–30 for which he served as president in 1926. He was knighted on 1 January 1927. He was also a delegate to Imperial Conference in 1930. He was one of the members of Second round Table Conference of India in 1931., Ottawa Conference of 1932 and World Monetary and Economic Conference in 1933. He was one of the experts on fiscal and tariff affairs and headed many committee. He published an essay on Railway Electrification and Industrialization, which work was later published by Indian Chamber of Commerece in 1945 In January 1945, an Iron and Steel (Major) Panel was set up by the then Government to recommend measures for the expansion of the steel industry, which was headed by him. Later, he was Chairman of Tarminal Facilities Committee in 1947.
Here is his speech in the Indian Legislative Assembly on 5 March 1923, it is about system of taxation:-
What takes place in the office of the Honourable the Finance Member every year when he prepares the revenue side of the Budget I can well imagine. He sits in his chair. He has got three men generally with him. On his right is perhaps Mr. Cook, on his left is Mr. Ayyar, and in front of him Mr. Sim. Then he asks, ' How much do these people require ? ' They say, * Oh, this year they want 80 crores 1 of rupees only from taxation'. 'Is that so ? What did they have last year ?' '64 crores.' ' Very well. Give me a copy of the Tariff Act, a copy of the Income Tax Act, and a copy of the Opium and the Salt Acts and a blue pencil.' He takes the blue pencil in his hands and says, ' Here, 11 per cent on this. No. I will put 15 per cent. That will give us 2 crores. Is that not so, Mr. Cook ?' * Yes, approximately that.' Mr. Sim then says, (Income Tax has been rather sterile these last few years. We will try a little super tax on something,' and he adds on something to the super tax. Then he goes through the Opium and Salt Acts, and the same process goes on until he thinks he has secured the additional sixteen crores. I submit that this is not the way in which, any longer, the Indian Budget ought to be prepared. Every country in the world has, at definite periods, undertaken an examination of the taxation of the country with reference to the taxable capacity of the people. They have got figures and they study all the conditions with reference to the requirements of the country. I maintain that though the Finance Department claims to know everything, they have got no data upon which they can determine the taxation with reference to the taxable capacity of the people. There, I submit, is the orthodoxy of the Budget."
In 1945 before independence of India, he settled in Calcutta. During 1949–1952, he served as Director of Indian Iron & Steel Co. promoted by Calcutta based industrialist, Sir Ranjen Mookerjee of Martin Burn. He also served as President of Calcutta based, the Indian Institute of Metals
He died in 1962.
In 1963 a gold medal was established by Indian Institute of Metals in his memory. The Sir Padamji Ginwala Gold Medal is awarded to recognise a candidate securing the highest marks in the Associate Membership Examination (Part-l) of the Institute.
His son Peston Padamji Ginwala (1918–2008) generally known as Pesi Ginwala was also a senior barrister working at Calcutta High Court. He had done his education from Charterhouse School, London, completed his law at Balliol College, Oxford and was called at bar at Inner Temple. He moved to Calcutta in 1945 and started his career at Calcutta High Court. He was noted for his legal acumen and expertise. He died in Kolkata in July 2008.
- Alumni Cantabrigienses: A Biographical List of All Known Students ..., Volume 2 edited by John Venn. 2011. p. 57.
- THE EDINBURGH GAZETTE, JULY 5, 1927.
- Indian Round Table Conference (Second Session) 7th ... by James Ramsay MacDonald – 1932 – Page 165
- Eastern economist by Eastern economist – 1963– Page 1277
- Industrialisation Through Electrification of the Railways: A Memorandum on the Conservation of Superior Grades of Coal and the Provision of Cheap Electricity for Industries and Agriculture by the Thermal Electrification of the Railways in Bengal and Bihar By Padamji Pestonji Ginwala, Indian Chamber of Commerce (India) Indian Chamber of Commerce, 1945 – Railroads
- Lok Sabha Debates by India. Parliament. Lok Sabha – 1965– Page 7298
- George Findlay Shirras (1936). Science of public finance, Volume 1. Macmillan and Co., limited. p. 6.
- "PESI GINWALA (1918–2008)". The Telegraph, Kolkata. 3 July 2008. Retrieved 26 February 2014.
- India at a glance: a comprehensive reference book on India by T. V. Rama Rao, G. D. Binani – 1954– Page 827
- Awards, Honors & Prizes: International and Foreign 1998 by Jack Batten – 1997– Page 389
- Indian Institute of Metals – Awards
- Sir Padamji Ginwala (1875–1962)
- The Parsees of Calcutta by Dalia Ray – 2005 – Page 56
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