It is alleged that the MLA abused the officer-in-charge of the East Agartala police station.
The two men had been detained in connection with an illegal lottery and forcible collection of puja subscriptions.
"Our party reprimanded Datta for such acts, and did not approve of the mistreatment and abuse of policemen," CPI-M state secretary Bijan Dhar told reporters.
Dhar, also a CPI-M central committee member, said: "Behaviour of our party men and legislators should not be like that of Congress men and other parties' members. What Datta has done could have been avoided."
The CPI-M leader alleged that many Congress leaders, including former chief minister Samir Ranjan Barman, had assaulted police officials and attacked police stations in the past, but the Congress leadership had remained silent.
The main opposition Congress has demanded legal action against the CPI-M legislator.
"Video footage showed that Datta abused the police officer in the police station itself, and took away the two detained persons forcibly," Congress spokesperson Ashok Sinha told reporters.
The Congress has also demanded that a case be registered against the CPI-M lawmaker.
"It is now clear that the CPI-M leaders have been patronising criminals in the state... chief minister Manik Sarkar is also responsible for such lawlessness," Sinha said.