Sharia police roam the streets of Indonesia's Banda Aceh province. They bust gamblers, drinkers, and adulterers and send them off to an "executioner" to be publicly caned.

Banda Aceh is the country's only province that has formally established Sharia law. But the policy is gaining strength in the Indonesian capital of Jakarta, breeding fear that the country’s long standing legacy of secularism could be at risk.

Syahrizal Abbas, the chief of the Aceh Sharia Agency, is instrumental in upholding Sharia law, like the caning of gay men up to 100 times, for example. "By the law of nature, it’s a violation. Therefore, God forbids it," Abbas explained.

The law's intolerance could also be empowering an extreme and dangerous minority: ISIS.

"The implementation of Islamic Sharia in Iraq, in Syria, is the system that best represents the Islamic law led by Sheikh Abu Bakr al-Baghdadi," said Syamsudin Uba, a radical Islamic leader, who was arrested in 2015 for publicly promoting ISIS. Baghdadi is the leader of ISIS, and last year, deadly twin bombings in Jakarta were promptly linked to the radical group.