The Senate has announced an inquiry into flag of convenience shipping after a Four Corners program earlier this month highlighted the suspicious deaths of three seafarers on board a Japanese-owned ship.

Over a six-week period in 2012, three crew members met their fate while working aboard the MV Sage Sagittarius, a giant transport ship which ferries coal between Australia and Japan.

On August 30, 2012, the ship was approximately 470 nautical miles from the Queensland coast when the chief cook Cesar Llanto disappeared. His body was never recovered.

Two weeks later, just as the ship was to dock at Newcastle port the chief engineer, Hector Collado, plummeted 11 metres to his death in the engine room.

An autopsy report later showed that Mr Collado had been struck on the head before he fell.

A third man, superintendent Kosaku Monji, who was assisting the investigation into the deaths, was crushed by the ships large unloading rollers while it was berthed in Japan in early October 2012.

The Sage Sagittarius is what the maritime industry has long called a "flag of convenience" (FOC) ship.

Although it belongs to a Japanese company, it carries the flag of Panama, allowing the company to reduce its tax burden and avoid exposure to more stringent workplace regulations.

Late last month, the NSW Coroners Court commenced hearing evidence into the deaths of both Mr Collado and Mr Llanto, who both died in Australian waters.

Counsel assisting the inquiry, Philip Strickland, told the court that the deaths were suspicious.

The Coroner also heard that the ship's captain, Venancio Salas, sold guns to the crew and had also allegedly bullied and physically assaulted the assistant cook.

The Senate inquiry will examine the national security, fuel security, environmental, social impacts of FOC shipping and will also revisit the 1992 Ships of Shame Inquiry.

"The murky world of flag of convenience shipping needs to be investigated," International Transport Worker's Federation coordinator Dean Summers said.
"Intimidation, bullying and harassment are often an unfortunate part of life onboard FOC vessels and it's allowed to happen because of jurisdictional blurred lines and a lack of regulation."

Late last month the Federal Government moved to deregulate Australia's shipping industry, which the Maritime Union of Australia believes will result in the loss of thousands of jobs and weaken labour and safety standards.

The Senate report is to be handed down in February 2016.