The Coalition Against Genocide (CAG) leaders have said brining to justice those responsible for the 1984 anti-Sikh riots would have deterred people from the 2002 riots in Gujarat.
"As disappointing as the Metropolitan Court's judgement is, it was sadly to be expected in a state that routinely denies justice for victims of Modi's government and his supremacist movement," said Shaikh Ubaid, a founding member of CAG, which is a broader coalition of over 40 US-based Indian American organisations.
On December 26, a Metropolitan court in Ahmedabad rejected a protest petition filed by Zakia challenging the clean chit given to 63 persons, including Modi, by the Supreme Court -appointed Special Investigation Team in the riots.
Zakia's husband Ehsan Jafri was among 68 people massacred during the Gulbarg society riots.
Meanwhile, the Indian National Overseas Congress (INOC) alleged that the expression of remorse by Modi in a blog is a cynical ploy.
"As we respect the judgement of the Court, this ruling may not be the final word on this matter and hope that Mrs Jafri will appeal against it in the higher court.
This verdict may also strengthen the suspicion of many that the victims may not get a free and fair trial as long as these cases are tried in Gujarat," INOC said in a statement.
"Modi's expression of remorse on the blog about the 2002 Gujarat riots is a cynical ploy to remove the stain from his shoulder and to bury that as an issue in the upcoming election where he is projected as the Prime Ministerial candidate by BJP," said George Abraham, chairman, INOC, USA.