The Kerala Union of Working Journalists issued a statement demanding that Solicitor General Tushar Mehta apologise for his "baseless criticisms" of the organisation.
"He should publicly apologise for trying to mislead the Supreme Court," the union's statement read.
During a Supreme Court hearing on transferring jailed journalist Siddique Kappan to a Delhi hospital for better treatment, Mehta had described the union as a "purported association...not even a well known one".
KUWJ pointed out that it had been working for 60 years for "the welfare rights of journalists in Kerala", working alongside the government to provide health schemes and pensions for members of the press. "The schemes are pioneering," the statement said, "and an example for the whole country."
It also noted that India's first press club owned by journalists themselves was set up by the KUWJ in Kochi.
The union said it would send complaints to the prime minister, the Chief Justice of India, and the attorney general, among others, asking that action be taken against Mehta.
Kappan was arrested in Uttar Pradesh in October while on his way to Hathras to report on the gangrape and death of a Dalit woman. He was charged with sedition and under the UAPA, and has been in jail ever since.
Earlier this week, the apex court said that Kappan, who is Covid positive, must be transferred from a Mathura hospital to a Delhi government hospital for treatment. Kappan's wife and the KUWJ alleged that he was being “chained like an animal” and had collapsed in the bathroom.