How borders are drawn and enforced has far-reaching consequences, whether we live on either side of them or halfway across the world.

Australian sex offenders convicted of crimes against children may be soon banned from leaving the country, their passports withheld by the government. It would be the first such restriction in the world, and could potentially affect 20,000 people currently on sex-offense registries.

The legislation, proposed by the Australian government, has yet to be introduced to parliament. It’s primary aim is to stop sex tourism, foreign minister Julie Bishop told reporters. About 800 registered sex offenders traveled abroad in the last 12 months, half of them to Southeast Asia, and half of them failed to notify authorities, as is required by Australian law.

In one widely-publicized case last year, an Australian man was convicted for assaulting 11 girls in Bali. “There has been increasing community concern about sexual exploitation of vulnerable children and community concern is justified,” Bishop said, according to the Associated Press.

The legislation will allow exceptions, for some business or family travel. Most of the offenders will be allowed to get their passports back after their requirement to be registered expires. About 3,200 people will be banned from traveling for life.

According to The Guardian Australia, there had been some concern among government officials about the restrictions’ effect on first-time offenders. This mirrors worries among a growing movement of sex-offender registry opponents in the United States. Often, people accused of far less than assault or molestation get caught in similar crackdowns.

“This will not apply to a teenager who has been caught sexting to his 15-year-old girlfriend,” said independent senator Derryn Hinch, a longtime campaigner against pedophilia in Australia.

In 2016, as an effort to fight sex trafficking, the US introduced through the so-called International Megan’s Law special stamps for passports of child-sex offenders. A legal challenge from a group of offenders who said they would be unjustly stigmatized and restricted failed in court.