Ferry companies have been accused of exploiting Ireland's vulnerability to Brexit to get the consumer rules they want.
In July, Irish Ferries, Stena Line and Brittany Ferries wrote to Taoiseach Leo Varadkar asking the government to intervene in a legal row over passengers compensation.
They claim they do not owe customers on cancelled ferries to France compensation because they can offer the option of using the "land-bridge' via Britain.
Labour's Transport spokesman Senator Kevin Humphreys said ferry operators should have the same responsibility to their customers as airlines.
He told Newstalk:
The three main ferry operators are exploiting a particular difficulty the Irish nation finds itself in, in relation to Brexit and seeking an interpretation of the legislation that suits themselves.
He added: "The same thing would have happened if somebody arrived out of Dublin airport and was flying to London and were handed a ticket to go and drive to London and say that's the normal air practise, it's not.
"People booked their holidays last year on the WB Yeats. They were entitled to believe that the company would have done due diligence before they took the bookings which obviously they hadn't and they were sorely disappointed."