The cruise ship carrying a New Zealand man who died after contracting coronavirus reportedly dropped off sick passengers days before disembarkation, but did not tell others there were any health risks on board.
Bob James is one of 16 Kiwis who have died after catching Covid-19 over the past month.
He and wife of 43 years Bev James were cruising on the Voyager of the Seas in mid-March, and just days after returning to their apartment at Coastal Villas in Raumati Beach were rushed to hospital.
Bob died several weeks later in Wellington Hospital after it was discovered only a small part of one of his lungs was still viable, having been ravaged by the virus. Bev has since recovered and is isolating in Kāpiti.
Her son, Brian Greenough, said the cruise ship travelled up and down the coast of New South Wales for several days before disembarkation, and reportedly even stopped to let off sick passengers - but other passengers were not made aware of any possible coronavirus cases on board.
His mother also told him the crew were called in for a staff meeting during the cruise, and afterwards she saw one crew member in tears.
The James family has been in touch with a lawyer in Sydney and they are looking into joining a class-action lawsuit against the cruise line, Royal Caribbean, over the handling of the matter.
Maritime lawyer Peter Dawson said criminal and civil cases against cruise lines relating to the Covid-19 crisis would need to determine who made the decision to continue the cruise instead of ending it early.
Such lawsuits, "particularly in maritime environments, are never straightforward", he said.
"You've got to establish what jurisdiction you are in, what court is it that's going to be looking at the potential liability of the owner, for a start."
One case currently under way was a criminal investigation by Australian Police into Princess Cruises' Ruby Princess.
The ship travelled to New Zealand and is responsible for starting a cluster of 22 cases after letting passengers off in Hawke's Bay.
It is also at the centre of one of Australia's largest clusters after thousands of passengers were let loose in Sydney.
A waiter or someone who handles food on the Ruby Princess was the likely source of a deadly outbreak of coronavirus in Australia, NSW Police earlier revealed.
Detectives are interviewing thousands of witnesses about what they knew about potential Covid-19 cases on board the cruise ship before it docked.
Since disembarking, at least 22 deaths have been linked to the ship and hundreds of confirmed cases.
NSW police announced a criminal investigation into the operator of the Ruby Princess, Carnival Australia, earlier this month, while Shine Lawyers in Australia have mounted a class action against the company, saying passengers were not advised of the risk and were not monitored for symptoms.
New Zealand is also exploring taking legal action regarding the Ruby Princess which visited five ports in early March. Sixteen cases in Hawke's Bay have been linked back to the ship which docked in Napier on March 14.
Dawson said action could be taken against the owner as well as the skipper and crew in cases against cruise ships.
"For the Ruby Princess, the police investigation that's being undertaken by the Aussies, it will focus on what choices the owner made and to what extent the management and the owner of the vessel were aware of the existence of the virus."
Then it would be a case of looking at whether the decision to continue cruising was made by the captain and crew, to determine where the liability lay.
"It's difficult to see the sequence of when the call was made and who has made it."
Running class actions was "quite a logistical exercise" because it could be difficult to assemble all the complainants and piece together their individual circumstances and details about who got sick and died. They would need to be able to show the impact on the complainants.
Meanwhile criminal liability was "very specific".
"You've got to show that a decision by person X caused the death of person Y, and that is to be beyond reasonable doubt."
A criminal investigation could end in fines or even imprisonment for those responsible, while civil action could end in awards to the complainants.
Dawson noted a civil suit brought in Australia would have significantly lower awards than one brought under a US jurisdiction.
Royal Caribbean has been contacted for comment.