In an interview with the BBC, he said that the laws were an outdated relic from the country’s colonial past.
Dr Sen was freed from jail in the state of Chhattisgarh earlier this month. He had been sentenced to life in prison in December for helping Maoist rebels.
The government is reportedly reviewing sedition laws.
Dr Sen also said the government was forming vigilante groups to fight the rebels. Villagers in some Maoist-affected areas have formed so-called self-defence groups, wihch have received state support.
The Indian government has repeatedly denied using unlawful means to fight the Maoists.
Worst affected
"I feel a great sense of vindication that I have been released," Dr Sen said, "as I was convinced that I did not commit any sedition, neither did I betray the nation nor the people of this country."
Dr Sen said that there were hundreds of people in Indian jails on charges of sedition.
"Such laws are being systematically misused to silence voices of dissent in our country," he said.
"I am pleased that the law minister has announced he will review the laws because they belong to the colonial past."
Earlier this month the Supreme Court granted bail to Dr Sen, saying that while he "may be a sympathiser [of Maoists]… it did not make him guilty of sedition".
Rights groups in India and abroad, along with 40 Nobel laureates, had called on the government to free him.
Dr Sen said that he fell foul of the government while working for the People’s Union for Civil Liberties in Chhattisgarh, one of the Indian states worst affected by the Maoist insurrection.
"In the course of our research we discovered that the government had embarked on a programme to finance vigilante groups.
"Because we raised our voices against such phenomena, we paid the price," Dr Sen said – in a reference to his recent prison sentence.
He said that vigilante groups in Chhattisgarh had operated without any institutional control, which is why the Supreme Court recently ruled that their formation was against the Indian constitution.
The human rights campaigner was also strongly critical of the ability of lower courts in India to handle sensitive criminal cases connected to the Maoist insurgency.
"We need a mechanism for monitoring cases handled by the lower judiciary," he said, "particularly those in which poor people cannot obtain proper legal advice and representation."