The Rajya Sabha will on December 17 debate and vote on the amendments to the country's counter-terrorism act.
The Human Rights Watch and other organisations claim that the amendments to the Unlawful Activities (Prevention) Act 1967, would allow the government broad leeway to increase bans on proscribed organisations to five years and widen the definition of a person to any association of individuals.
The Lok Sabha had passed the amendments on November 30.
"While India has a responsibility to protect citizens from terror attacks, the counter-terrorism law has long been abused to detain suspects for excessive periods, file charges on fabricated evidence, and ban organisations without due process of law," Meenakshi Ganguly, South Asia director at Human Rights Watch, said.
"These amendments will make the law an even more dangerous tool in the hands of officials who seek to oppress peaceful critics and minority communities."
The UAPA and counter-terrorism laws preceding it have been widely misused to target political opponents, tribal groups, religious and ethnic minorities, and Dalits, Human Rights Watch said.
Citing an instance, HRW said that state police have used the UAPA bans on groups to round up the same suspects after every terrorist attack simply because they had been previously charged, but not convicted of membership in an unlawful organisation.
The proposed amendments expand the definition of the "person" who can be charged under the law to include "an association of persons or a body of individuals, whether incorporated or not."
According to HRW, this would allow the police to charge an individual merely on grounds of contact with a suspect.
The amendment increasing the period for which an association can be declared as unlawful from two years to five years will allow the authorities to ban for a longer period an organisation it opposes, even though the organisation has not been found unlawful by a court, it added.
"Extending the ban on groups from two to five years without court determination is a recipe for abuse," Ganguly said, adding, "The police and investigating agencies could arrest people for being part of a banned organisation even though a court never found it to be involved in terrorism."
The amendments also expand the definition of "terrorist act" to include acts that threaten the economic security of India and damage its monetary stability by production, smuggling, or circulation of "high quality" counterfeit currency.
These crimes are not recognised terrorism offenses and are already covered by the Indian Penal Code. Including them under a more stringent counter-terrorism law seems intended to make obtaining bail more difficult and to allow for a longer pre-charge detention period, HRW says.
When Opposition members called for a more thorough discussion of the amendments, Home Minister Sushil Kumar Shinde told Parliament that the government would never allow the misuse of the law and that the amendments would bring clarity to the existing framework and remove deficiencies.
"Bad laws not only violate international human rights standards, but are counter-productive, as abuses are used as a recruiting tool by extremist groups," the NGO further states.
The 2008 UAPA amendments also increased the risk of arbitrary detention, custodial abuse, and violation of basic due process rights by allowing courts to double the maximum period of detention without charge for terrorism suspects.
A judge can extend pre-charge detention from the 90 days allowed under the Indian criminal code to 180 days upon a vaguely-defined special request from a prosecutor.
The law also doubles the maximum period of police custody from the 15 days allowed under the Indian criminal code to 30 days.