Abdur Rahman has been speaking out against the bill since it was introduced in Lok Sabha on Monday.
An Indian Police Service officer of the Maharashtra cadre on Wednesday announced his decision to quit government service in protests against the Citizenship (Amendment) Bill or CAB which he said was "against the basic feature of the Constitution".
Abdur Rahman -- who is currently posted in Mumbai -- announced his resignation and condemned the bill on Twitter, minutes before it was cleared by the Rajya Sabha on Wednesday. The controversial legislation was passed by the upper house with a vote of 125 against 99, two days after it sailed through the Lok Sabha.
"The #CitizenshipAmendmentBill2019 is against the basic feature of the Constitution. I condemn this Bill. In civil disobedience I have decided not attend office from tomorrow. I am finally quitting the service," he tweeted, along with pictures of his resignation letter.
Mr Rahman is an Inspector-General of Police or IGP rank officer in the Maharashtra State Human Rights Commission. In another tweet, he said: "This Bill is against the religious pluralism of India. I request all justice loving people to oppose the bill in a democratic manner. It runs against the very basic feature of the Constitution."
Mr Rahman has been speaking out against the bill since it was introduced in Lok Sabha on Monday. He even accused Home Minister Amit Shah of distorting history, and presenting "misleadingly information".
The Citizenship (Amendment) Bill seeks to make it easier for non-Muslim migrants from Pakistan, Afghanistan, and Bangladesh who entered the country before 2015 to become Indian citizens. Opposition leaders, who claim that the bill can never survive "judicial scrutiny", are expected to challenge the bill in the Supreme Court.