Hundreds of passengers who are arriving in Ireland are not filling out their details or responding to follow up calls, it has emerged.
The Department of Justice has confirmed that 34% of the 670 passengers who arrived at Dublin Airport over a six-day period did not complete a form saying where they would be staying.
And 36% of those who did fill out their details have failed to respond to calls checking on their isolation status.
Everyone who arrives into Ireland is expected to go into self-quarantine no matter where they came from.
The Department of Health offers the public health passenger locater form to travelers which asks them to fill in their names, address, travelling companions and where they can be contacted so officials can check up on them.
However, they don't have to complete the form and the request is not supported by any laws.
The Department of Justice also said a quarter of those coming in at Dublin Port who were asked to self-isolate did not respond to follow up check calls.
Nearly nine in 10 of those entering Ireland via the port are supply chain workers who do not need to fill out the form.
But the Department of Justice said that 26% of those required to self isolate failed to respond to calls.
The Department said it is awaiting the full returns from other airports and ports nationwide such as those Rosslare, Shannon and Cork.
"The Department of Health says the issue is being examined across a number of departments and the Government is currently examining the drafting of regulations to underpin the administrative requirements now in place."
Irish Council of Civil Liberties chief Liam Herrick has said it is "certainly possible" for the State to enforce people to give information.
Mr Herrick told RTÉ Radio 1's Today with Sean O'Rourke the 'unwieldy' legislation in place since March 20 has already given the Government the power to introduce laws over entry to Ireland, but he claimed "it has chosen not to do it up to now".
He added: "If you are going to go down that road and make the choice to go from voluntary to a mandatory system that there are processes to ensure you do it properly."
