Basuki Tjahaja Purnama, universally known as Ahok, posed gallantly for photos with detention centre staff, in what one Twitter wag described as "peak Indonesia".

These photos quickly circulated on line along with the hashtag #RIPHukum, which means "RIP to the law".

There have been outpourings of grief at candlelit vigils spanning the archipelago from Bali to Papua. They have even gone international - the Indonesian diaspora in Australia have organised events in Melbourne, Sydney and Perth on Saturday and Canberra on Sunday.

Vice-Governor Djarot Saiful Hidayat wept openly at a choir outside City Hall, offering to be a guarantor for Ahok's release from jail while he appeals his sentence.

"If anything happens, I'll go to jail," he pledged.

He was jailed for two years on Tuesday, not for corruption but for telling people to vote with their conscience, albeit in a provocative and foolish way.

While campaigning for re-election in September, Ahok - himself a Christian and ethnically Chinese - was critical of his political opponents who used verse 51 of al-Maida - a chapter of the Koran - to persuade voters not to support Ahok because he was non-Muslim.

His opponents, including hardline groups such as the Islam Defenders Front (FPI) and Hizbut Tahrir Indonesia (HTI), staged massive rallies calling for his prosecution, paving the way for his blasphemy trial.

Ahok is not the first Chinese Christian to be found guilty of insulting Islam under Indonesia's blasphemy laws, but he is undoubtedly the most high profile.

The laws generally target those belonging to minority faiths, such as Ahmadis and Shiites, whose interpretation of Islam deviates from the mainstream Sunni Islam of Indonesia.

However the most prominent case prior to Ahok's was the five-year jail sentence given in 1991 to Arswendo Atmowiloto, the chief editor of the Jakarta tabloid journal Monitor, who published a poll on readers' "most admired people" which rated the Prophet Muhammad 11th among 50 names.

In March this year, three ex-leaders of Gafatar, which Islamic clerics had called a "deviant sect", were jailed for up to five years after judges found the movement offended Islamic values. The court noted prayers were not obligatory in the Gafatar movement.

However it was Ahok's unexpectedly harsh sentence - prosecutors concluded he did not intend to insult Islam and did not request that he be jailed - that sent ripples of shock throughout the world.

The European Union issued a statement saying laws that criminalised blasphemy, when applied in a discriminatory manner, could have a serious inhibiting effect on freedom of expression and religion.

Britain's first Muslim ambassador to Indonesia, Moazzam Malik, tweeted that he knew and admired Ahok and did not believe he was anti-Muslim. This is highly unusual, given diplomats are normally at pains not to comment on the domestic situation in their host country.

The United Nations called on Indonesia to review its blasphemy laws.

"Actually we don't need such a rubbery law any more. It is only used to serve certain political targets," Yahya Cholil Staquf, the Supreme Council General Secretary of Indonesia's largest Islamic civil organisation, Nahdlatul Ulama (NU), told Fairfax Media. "What happened with Ahok actually shows that this law has numerous flaws."

In a rousing editorial in The Jakarta Post, editor-in-chief Endy Bayuni said Indonesia had come too far on the march towards democracy begun in 1999 to give up now.

Supporters of Basuki Tjahaja Purnama, also known as Ahok, outside Jakarta City Hall on May 10. Photo: Jefri Tarigan

"Ahok's guilty verdict was surely a tragedy for democracy," he wrote. "This is no time for regrets however. What is required is hard work on our part to get back to where we were before ??? One priority area is to get the Constitutional Court to repeal the blasphemy legislation because it has been widely abused and has sent the wrong people to jail."

But Andreas Harsono, a senior researcher at Human Rights Watch, is pessimistic about the likelihood of the blasphemy laws being repealed.

Indonesia's 1945 constitution explicitly guarantees freedom of religion but the government only recognises six official faiths: Islam, Catholicism, Protestantism, Confucianism, Buddhism and Hinduism.

In 1965 Sukarno, the first president of Indonesia, enacted blasphemy laws to prevent "deviation" and protect religious harmony, amid concerns religions could be tarnished by mystical indigenous beliefs.

However only a handful of people were prosecuted until Susilo Bambang Yudhoyono became president in 2004. During his 10-year reign about 100 people were charged with blasphemy, all of whom were found guilty.

In 2009 activists, including former president Abdurrahman Wahid, asked the Constitutional Court to repeal the blasphemy laws, arguing they breached the right to freedom of religion.

However the court found the laws were necessary to maintain public order.

"In 2009 when the law was challenged, it was the Islamists with the backing of SBY who defended the laws," Harsono told Fairfax Media. "I think the Islamists are only getting more powerful."

Harsono worries the next target of hardline Islamist groups will be the Christian governor of West Kalimantan, Cornelis, who has publicly warned anyone who is radical or intolerant to leave the province.

His fears have already been realised - during a visit by Cornelis to Banda Aceh last week, a group calling itself the Islam Defender Troop (LPI) went to his hotel and demanded he leave the city.

"Aceh land is haram (forbidden) for those who hate ulema (religious scholars) and Islam, including Cornelis," one protester, Tengku Achmad Shanjy, was quoted as saying in The Jakarta Post.

In an interview with Fairfax Media this month, Prabowo Subianto, who is widely tipped to challenge President Joko Widodo in the 2019 election, said religion was a sensitive subject in Indonesia.

He cited the 2013 case of Rusgiani, a Christian who was sentenced to one year and two months' jail in Bali. She had described canang sari - the daily offerings Balinese Hindus place in temples or small shrines in houses to thank the deity - as "dirty and disgusting".

"In recent years there were several other cases which maybe for foreigners or for people who were educated outside of Indonesian environment and culture and tradition seem to be very small," Prabowo said. "But it is so sensitive."

But most analysts and human rights organisations fear the Ahok verdict ushers in a dark new epoch for Indonesia, where non-Muslims are lesser citizens and religion can be used as a tool for subjugation.

A few careless throwaway lines on the campaign trail, whipped into an outrage by his foes, cost Ahok his bid to be re-elected as governor and two years behind bars.

The NU's Yahya Cholil Staquf believes religion was exploited not just by radical groups but by craven politicians who used their resources to mobilise people to attend the anti-Ahok rallies.

He says the Ahok case verdict will tempt opportunistic politicians to continue to use religion to achieve their political goals. "It has been proven it works," he says. "And this is going to be dangerous for the future unity of the nation."

But while there have been volumes of commentary on the political dimension, Dr Melissa Crouch, an expert in Indonesia's blasphemy laws from the University of New South Wales, says there has been surprisingly little commentary on the role the courts played in Ahok's downfall.

Crouch says the prosecution request that Ahok only be given a suspended sentence seemed like a rather convenient concession to the embattled governor, coming a day after his resounding loss in the gubernatorial election.

Rizieq Shihab (with microphone) speaks in Jakarta in January. His role in the blasphemy trial of Ahok has been criticised. Photo: Dewi Nurcahyani

"The courts, it seems, were not having any of this," she writes in Policy Forum. "Indonesia's judges are fiercely protective of their independence, to a point that it now borders on a gross lack of accountability."

She also wrote that it was cause for alarm that firebrand Islamist Rizieq Shihab, the leader of the Islam Defenders Front who has been jailed twice for inciting violence, was called as an "expert witness" during the trial.

Three of the five judges in Ahok's blasphemy trial were promoted the day after the verdict.

Crouch believes there is a glimmer of hope for Ahok. The staff of a controversial Islamic drug and cancer rehabilitation centre at Probolinggo were jailed for more than four years for writing a book called Through the darkness towards the light, which was judged heretical. "They were acquitted on appeal," she says.

Ahok has the advantage of wealth, resources and the adoration of millions of people. As the flyer for Saturday's Ahok Unity March in Perth says: "Pak Ahok, you'll never walk alone."

"I am worried about the orang kecil [little people] who may fall victim of this law such as Ahmadiyah, Shiite, Gafatar etc," says Bonar Tigor Naipospos, the head of the Setara Institute for Democracy and Peace. "They don't have big support."

with Karuni Rompies

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