"We have leveled the playing field so the laws suit the majority, not the minority," state Attorney General and Justice Minister Jarrod Bleijie said in a statement at the time.

The Queensland Supreme Court subsequently overturned the appeals court ruling anyway, saying in May that Drovers Rest did have the right to deny Karlaa a room, even before the law was amended.

Tougher limits on prostitution are also on the table in the state of Western Australia, where iron ore is excavated from its sparsely populated north. Proposed laws would limit the sex trade to a few designated areas and require self-employed sex workers to be licensed. No more than two such licensed prostitutes could work from the same premises.

John Scott, a criminologist at Australia's University of New England, said that Queensland and Western Australia are tightening restrictions after a loosening of controls by Australian states that began in the 1990s.

"There does seem to be a reverse trend in both those mining states, and I suspect part of it relates to the mining industry and some of the concerns raised in rural areas," Scott said.

The FIFO sex workers tend to be older than their city counterparts and don't dress as provocatively. With housing tight, some arrive in motor homes or sublet spare rooms in clients' homes. They advertise in newspapers and on websites, and have even handed out fliers at Moranbah's main shopping mall.

Karlaa, who lives more than 1,000 kilometers (600 miles) away in the tourist city of Gold Coast, said she used to send text messages to regular clients announcing the dates of her next visit. Word would quickly spread among hundreds of men across mine sites by two-way radio.

Another Gold Coast-based sex worker said she doesn't plan to return to Moranbah because escorts are made to feel unwelcome. The woman, who is in her early 20s, said young and attractive sex workers are particularly conspicuous and likely to be given a room near the reception if they stay at Drover's Rest, so they can be kept under surveillance. She continues to work in other mining towns in the region.

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