"I always feel that Mrs (Indira) Gandhi was a democrat at heart," Sonia told The Guardian, as reported by news agency PTI.
"I know that many would laugh at this, but I believe she was never comfortable in the course of the emergency. I think it was sitting heavy on her," she added.
According to The Guardian, Sonia acknowledged that imposing the Emergency was a mistake and expressed her belief that Indira Gandhi eventually recognised this.
Emergency divided the Gandhi family
Sonia's account also reveals disagreements within Indira Gandhi's family over the decision.
According to The Guardian, her husband Rajiv Gandhi opposed the Emergency and advised his mother to wait for the next general election.
His younger brother Sanjay Gandhi, however, reportedly supported tougher action against the opposition.
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During a family dinner, Sanjay allegedly warned that opposition leaders would destroy Indira Gandhi unless they were stopped.
"They must be stopped," Sanjay reportedly told his mother.
Sonia recalled that Rajiv attempted to confront Indira over the decision, but she refused to listen.
"Keeping Sanjay in check could have prevented much of the damage that followed," Sonia writes in her memoir, according to The Guardian.
Did Indira Gandhi regret the Emergency?
In a separate interview with The Hindu, Sonia said hindsight had helped her understand the political circumstances surrounding the Emergency.
She pointed out that Indira Gandhi subsequently acknowledged the excesses committed during the period.
"And you know very well that she herself later publicly expressed regret and apologised for excesses during the Emergency," Sonia said.
However, Sonia also clarified that Sanjay Gandhi was not solely responsible for the developments.
She said several senior Congress leaders had pressured Indira, while relatively few people, including Rajiv, expressed opposing views.
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What happened during the Emergency?
Indira Gandhi imposed the Emergency on June 25, 1975, leading to restrictions on civil liberties, political opposition and press freedom.
The period also witnessed the suspension of habeas corpus protections and arrests of opposition leaders.
On January 18, 1977, Indira announced fresh elections. Congress subsequently suffered a major defeat, and the Emergency officially ended on March 21, 1977.
Sonia's disclosures come amid continuing political debate over the Emergency, which the BJP has repeatedly described as a dark chapter in Indian democracy.
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