India's decision to block an American fact-finding mission on religious freedom from entering the country is the latest illustration of Indian Prime Minister Narendra Modi's dubious track record on religious freedoms, said experts and activists.

"It might be interpreted that his [Modi's] government might have something to hide," Meenakshi Ganguly, South Asia director for Human Rights Watch, told VICE News.

The controversy began on Thursday when the obscure US Commission on International Religious Freedom, or USCIRF, announced that India had denied its members visas to enter the country. Established by the United States Congress in 1998, the commission monitors violations of religious liberty around the globe and offers advice to the president.

"As a pluralistic, non-sectarian, and democratic state, and a close partner of the United States, India should have the confidence to allow our visit," said Commission Chairman Robert George in a press release.

Countries with less-than-stellar track records on religious tolerance like Myanmar, China, Pakistan, Saudi Arabia, and Vietnam have admitted commissioners in the past, George said. "One would expect that the Indian government would allow for more transparency than have these nations," he said in his release.

In response, the Indian Embassy in Washington, DC issued a statement that reaffirmed India's dedication to diversity. Technically, the Indian government is secular.

"India is a vibrant pluralistic society founded on strong democratic principles," the embassy statement said. "The Indian Constitution guarantees fundamental rights to all its citizens including the right to freedom of religion."

But the embassy officials also dismissed the commission out of hand. "We do not see the locus standi [legal standing] of a foreign entity like USCIRF to pass its judgment and comment on the state of Indian citizens' constitutionally protected rights," the statement said.

Left unsaid in the back and forth were allegations that Modi's critics have repeatedly levied against the prime minister. Elected in 2014 on a platform of improving India's business climate and its stature on the world stage, Modi has also been accused of promoting India's majority religion of Hinduism to the detriment of Christianity, Islam, and other faiths. Around 80 percent of Indians are Hindu.

The criticisms start with the Gujarat riots of 2002, when Hindus went on a rampage for weeks, killing at least 1,000 Muslims while Modi, who was governor at the time, allegedly declined to restore law and order in the streets. A government investigation cleared him, but the incident is a black spot on his career.

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"There was, if not complicity — and there is no smoking gun — there was certainly incompetence in not being able to contain the violence," said Ganguly.

More recently, a wave of bizarre religious incidents involving Modi's Bharatiya Janata Party and Hindu nationalist groups that are affiliated with the party, like the Rashtriya Swayamsevak Sangh and Vishva Hindu Parishad, have also raised serious questions about Modi's rule.

Those incidents include Bharatiya Janata Party leaders supporting a mob of angry villagers who lynched and killed a man in Uttar Pradesh in northern India last year because he was thought to be keeping beef in his refrigerator. To Hindus, the cow is sacred. The meat turned out to be mutton.

Vishva Hindu Parishad groups have staged mass conversion ceremonies called "homecomings" that aim to turn Christians, Muslims, and others into Hindus. The groups claim that the converts' ancestors must have been Hindus in the past, so they in a sense are being brought "home." But some of the converts have complained they were tricked into changing religions.

And Rashtriya Swayamsevak Sangh members have sought to reform the Indian education system to include incredible Hindu nationalist interpretations of history, including how stem cell technology can be traced to the Mahabharata, an ancient Hindu epic. Modi has endorsed those claims.

The USCIRF has documented sectarian violence in India that commission researchers claim has increased under Modi.

'It might be interpreted that his government might have something to hide.'

"Christian communities, across many denominations, report an increase of harassment and violence in the last year, including physical violence, arson, desecration of churches and Bibles, and disruption of religious services," said the commission's 2014 report on India.

The report outlines similar mistreatment of Muslims, including indiscriminate imprisonment of young men on terrorism charges, and of Sikhs, who face harassment for wearing their hair unshorn and the kirpan, a religious dagger that devout Sikhs carry at all times.

Modi has never condemned these developments or addressed them as a national problem, said Gautam Adhikari, the former executive editor of The Times of India who is now a senior fellow at the Center for American Progress.

"Hindu nationalists believe they deserve the country to be primarily a Hindu nation and everyone else can live there, but only under the framework of Hindu nationalism," Adhikari told VICE News.

Indian bureaucrats commonly deny visas to commissions like the USCIRF, said Adhikari. Steeped in anti-colonial thought, they don't like taking criticism from the West. Adhikari figured this decision wasn't routine, however.

"To take a decision on a Congressional commission I think it would require political approval right up to Mr. Modi's level," he said. "It would be difficult for a set of bureaucrats who normally decide on issues like visas to refuse something that is sanctioned or at least established by the US Congress."

It wasn't the first time the USCIRF has been blocked. In 2009, the government of Modi's predecessor Manmohan Singh, a Sikh and member of the secularist Indian National Congress, also denied entry visas to the commissioners.

But Hindu religious leaders might have played a role in that incident.

Adhikari's former newspaper, The Times of India, reported at the time that Hindu pontiff Shankaracharya Jayendra Sarawati said the USCIRF should not enter the country because it was an "intrusive mechanism of a foreign government which is interfering with the internal affairs of India."