British academic Nitasha Kaul has long researched the changing social and political landscape in India.
It's led her to a dire conclusion about the world's most populous democracy.
"What we're witnessing post-2014 is a democratic erosion in India — that is undeniable," Professor Kaul told the ABC.
More than 950 million Indians are eligible to vote in this year's general election which began last week, and is held in seven phases until June 1.
Prime Minister Narendra Modi is expected to easily win a third term in office after first coming to power in 2014.
But ahead of the critical poll, Professor Kaul was shocked when she was barred from entering the country.
In February, she was detained and then deported after being invited to speak at a conference on the country's constitution, despite holding a valid lifelong visa.
She said no reason had ever been given for the decision.
"If you are critical of a political project, or a political party or their policies, it should be very straightforward that you're not against the country," she said.
"What … these kinds of actions do is label people as anti-national for being critical of a party or of its policies or a leader."
Professor Kaul held an Overseas Citizens of India (OCI) card.
Indian citizens can only hold one passport, but the OCI card acts as a lifelong visa, allowing foreign nationals of Indian origin to reside and work in India.
Professor Kaul's experience isn't an isolated one.
Research by the pro-democracy group Article 14 found at least 102 people have had their OCI cards revoked since 2014 under a clause of the country's citizenship laws.
The clause allows the government to cancel an OCI for several reasons, including if they have "shown disaffection towards the Constitution of India".
A Human Rights Watch report found several high-profile academics — who had published research critical of Indian government policy, Mr Modi or had commented on big issues affecting the country — were among those barred from entering India.
The report noted that in addition to cancelling OCI cards, the Indian government downgraded the privileges of 4.5 million OCI cardholders in 2021.
That move meant they needed to seek special permission to carry out tasks like research and journalism or visit areas in India listed as "protected".
Reducing public debate in India
Professor Kaul is the chair of the Centre for the Study of Democracy at the University of Westminster and has written extensively on how India's political landscape has changed since Mr Modi came to power.
She has also written about rising authoritarianism in the country.
After going public about her experience, she said other academics expressed concern their work would be a barrier to them getting home to see family.
[TWEET]She said the government's aim was to ultimately reduce the size of the public sphere in which to debate policy and publish academic work.
"This is a classic kind of authoritarian thing to be doing," she said.
Professor Kaul also received "violent, vicious, extremist, misogynistic, graphic sexual trolling" and death threats online.
"The idea for people who do that to people who are in the public domain is to try and intimidate and silence them," she said.
At the time Professor Kaul was denied entry, India's Ministry of External Affairs said "entry of foreign nationals into our country is a sovereign decision".
'Grossly unfair'
London-based writer and activist Amrit Wilson's OCI card was cancelled two years ago.
She was born in India but moved to the United Kingdom when she was in her 20s, keeping close ties to her home nation.
Ms Wilson said the government attributed the cancellation to an article she wrote about protesting Indian farmers and a social media post about the Muslim-majority region of Kashmir.
She's challenging the cancellation.
"It seemed grossly unfair," Ms Wilson told the ABC.
"The government can't handle dissent of any type. It locks dissenters up and if they're abroad it tries to target them in other ways."
The Indian government was contacted for comment on why it was cancelling OCIs.
Opposition MPs have been arrested, protesters have been detained and internet shutdowns have targeted anti-government commentary in the lead-up to the national election.
Reporters Without Borders ranked India 161st of 180 countries and territories in its latest World Press Freedom Index.
Human Rights Watch's Asia director Elaine Pearson said other countries should hold India to account.
"These governments should press the Modi administration to interact with its critics to bring about reform, instead of intimidating them into silence," Ms Pearson said.
Rising Hindu nationalism
Mr Modi's grip on political power is intricately connected with religion and a rising anti-Muslim sentiment in India.
India is still officially a secular nation, and while Hinduism is the biggest religion, the country is home to 200 million Muslims.
Despite that, Mr Modi hasn't hidden his Hindu nationalist ideals.
In January, he inaugurated a Hindu temple built on the site of a demolished mosque, delivering on one of his earlier poll promises.
His government has also moved to enact a law that fast-tracks naturalisation for people who have fled from religious persecution in Afghanistan, Bangladesh and Pakistan but excludes Muslims from those countries.
In 2019, he stripped the Muslim-majority region Kashmir of its special status, bringing it under Delhi's control.
Ms Wilson said there was a concerted attack on Muslims, aiding the government and Mr Modi's political agenda.
"Modi plays to the Hindu majority by creating a fear of Muslims," she said.
"He concocts all kinds of lies about the Muslim population, and people do fall for it."
Last week, India's main opposition party accused Mr Modi of using hate speech after he called Muslims "infiltrators" at an election rally.
Mr Modi's Bharatiya Janata Party denies accusations of fostering religious intolerance and says its policies benefit all Indians.
India Hate Lab, a website tracking hate speech in India, found a steep rise in hate speech targeting Muslims in the second half of 2023.
It documented 413 incidents, a 62 per cent rise compared to the first six months of the year.
