Michael Bachelard – By western standards, the rooms are dingy, but Aceh's love hotel is doing a roaring trade.

"Fauzi", 45, who regularly brings his 25-year-old girlfriend to this motel-style hideaway in the suburbs of Banda Aceh, says he's not interested in luxury anyway. "All I need is a bed, air conditioning and a toilet."

And it also has the benefit of being safe. "The military owns it," Fauzi says, "so the sharia police never disturb you here."

Aceh is the only province of Indonesia where sharia (Islamic law) is imposed. It was put in place under a special deal with Jakarta in 2001 as the central government tried to placate a violent rebellion in its westernmost province.

In practice, the law focuses on criminalising three infractions: drinking, gambling and unmarried couples being in "close proximity". Each is punishable by caning, a big fine or even imprisonment and the law is patrolled by a special force of moral police in uniforms.

But an attempt two years ago to extend it so adulterers could be stoned to death faltered because governor Irwandi Yusuf refused to sign the law. Campaigns by the sharia police to prevent women wearing tight jeans come and go. Under these restrictive circumstances, a discrete place for unmarried sex is in hot demand.

Fauzi says he will continue coming here until his divorce is finalised and he can marry his girlfriend and move in with her. "Everyone comes here," he says. "Married, not married, military, police, civilians," he says.

A prayer mat is in the cupboard to cater for the devout. On our brief visit, several couples were coming in and out of rooms. The car park was full, its attendant busy.

All around Aceh, which goes to the polls today, are the signs of the restrictions of Islamic law. Almost every woman wears a jilbab – an open-faced hair covering. In public places where young people gather signs warn them to behave.

"No dating," says a crudely painted one at a favourite fishing spot. "Those who are not husband and wife are not permitted to sit together. Those who break this rule will face the risk," reads another.

But all around this city is evidence of people slyly subverting the rules. Young women grip their young men slightly too fervently as they sit on the back of their motorcycles; watchful couples hold hands or cuddle in the half dark of the beachfront at Ulele.

Rahman, 23, and Juniar, 21, unlike many couples on Banda Aceh's waterfront, are engaged, and their parents approve of their liaison. But even so they were moved on by a sharia policeman a few months ago.

"I said to him, 'What business do you have asking us to leave'?" Juniar recalls. "He said, 'You are my business'."

They, like all their friends, are keenly aware of where the boundaries lie and what they can get away with. Nobody wants the shame of a public caning. Some who have been punished are forced to move away from their village.

Fauzi says that if you polled the public, only 10 per cent would say they wanted sharia, "and they would all be over 50".