Schapelle Corby return: Australia's most infamous accused drug smugglers.

Schapelle Corby’s conviction for attempting to import drugs into, or out of, a foreign country is a cautionary tale — but not an uncommon one.

Latest figures by Department of Foreign Affairs and Trade show over 40 per cent of Australians imprisoned overseas have been convicted of drugs offences.

Reports by the New South Wales Council for Civil Liberties show at least 20 Australians are, or have been on, death row for drug-related offences since the early 1980s, resulting in six executions.

Often in their early 20s, the individuals almost all claim to be unwitting drug mules or victims of complex crime syndicates.

As the country reacts to Ms Corby’s return, we revisit six infamous cases.

Kevin Barlow and Brian Chambers, Malaysia

The two Perth men were the first westerners to be hanged under Malaysia’s tough anti-drug laws for heroin trafficking in 1986, aged 28 and 29.

Barlow and Chambers were caught carrying 180 grams of low-grade heroin hidden in a suitcase. A policeman had noticed Barlow’s nervous behaviour.

Reports suggest the pair was persuaded by John Asciak, a key figure in a Perth-based crime syndicate, to make the trip.

A subsequent appeal on the death sentences failed, as well as clemency appeals on behalf of then Australian prime minister Bob Hawke and British PM Margaret Thatcher.

Status: Executed by hanging

Martin Garnett, Thailand

Now aged 50, the former luxury car salesman holds the record for the longest overseas incarceration, having spent over 20 years in prisons across Thailand, the United States and Australia.

Garnett was arrested in 1993 in Bangkok as he attempted to transport almost five kilograms of heroin strapped to his body, destined for New Zealand.

While initially handed a death sentence, the penalty was later commuted to 40 years.

During his sentence he performed a hunger strike that lasted 31 days.

In 2011, he was extradited to the United States for running a separate international drug smuggling ring from inside a Thai prison.

Garnett’s pensioner mother then crowd-funded $20,000 so her son could serve out the remainder of his sentence in Sydney, and he was let free in 2015 after 22 years.

Status: Released

Gordon Vuong, Cambodia

Vuong was just 16 years old when he was caught in Cambodia for trying to transport over two kilograms of heroin in 2005.

Arrested as part of a drug syndicate with two others, traffickers had promised to pay the young Sydneysider $1,300 when he made the drop.

To the anger of many civil liberties groups, Vuong was initially interrogated by police without an adult, lawyer or embassy official present, and subsequently sentenced to 13 years in a Cambodian prison.

It was also later discovered Vuong had been caught based on information provided by the Australian Federal Police.

Then justice minister Chris Ellison attempted to negotiate a prisoner exchange, but to no avail.

The 28-year-old is set to be released next year.

Status: Imprisoned

Andrew Chan and Myuran Sukumaran, Indonesia

Chan and Sukumaran were convicted of leading the Bali Nine heroin smuggling ring, found guilty in 2006 of providing money, airline tickets and hotels to drug mules.

The operation was an attempt to traffic $8 million worth of heroin to Australia.

Despite several judicial appeals, a clemency bid and pleas by both prime ministers John Howard and Tony Abbott, the co-ringleaders were killed by firing squad at Indonesia’s maximum security prison on Nusakambangan island in 2015.

Six other Australian ring members were handed life sentences, while one person was given a 20-year sentence.

Status: Executed by firing squad

Peter Gardner, China

The dual Australian and New Zealand citizen allegedly attempted to smuggle 30 kilograms of crystal methamphetamine onto a flight to Sydney in 2014.

The haul was found after officials pried open Garner’s superglued suitcases, but he claimed he thought the bags contained performance-enhancing peptides.

Now 28, Gardner is still awaiting official charges in a Guangzhou prison.

He potentially faces the death penalty, as Chinese law states anyone caught with 50 grams or more of heroin or methamphetamine is liable for capital punishment.

Status: Awaiting trial

Cassie Sainsbury, Colombia

The Adelaide woman was arrested in April this year after she was found with 5.7 kilograms of cocaine at El Dorado International Airport in Bogota.

Sainsbury’s family claim she was “naïve” and only accepted the packages containing the drug because she believed they were headphone earpieces.

Despite assistance from the Department of Foreign Affairs and Trade, Sainsbury has been denied bail and potentially faces 25 years in prison.

She now awaits a trial due in just over a month in the El Buen Pastor women’s prison.

Status: Awaiting trial

This post originally appeared on ABC News.