An Irish man whose father is critically ill has taken legal action in an attempt to avoid having to undergo mandatory hotel quarantine, when he arrives in Dublin from New York in the morning.

Colm Bates is travelling to Dublin to see his 91-year-old father who is "on his deathbed", the court heard.

Mr Bates' mother died last April and he was unable to get home for her funeral because of restrictions on flights due to Covid-19.

His Senior Counsel, Mícheál P O'Higgins, said Mr Bates was very distressed by that and does not want the same thing to happen in relation to his father.

Mr Bates is due to leave New York on a flight tonight and is due to arrive at Dublin Airport at 4.50am with a return flight booked for 7 May.

He has had a Covid-19 test and tested negative three days ago. He has also received his first dose of a Covid-19 vaccine.

The judge will hear his application in full in the morning.

In a sworn document, the court was told Mr Bates has lived in New York since 1996 and works as a project manager for a construction development company.

His solicitor, Michael French, wrote to the Department of Health last Wednesday seeking an exemption from quarantine on humanitarian grounds. But a reply said there was no facility for a review of detention before travelling, or in Dublin Airport.

The court heard Mr Bates' father is critically ill, is not expected to recover, and the family had been asked to gather. Family members are permitted to visit him in hospital in groups of two.

Mr O'Higgins said Mr Bates "deeply and profoundly" regretted not being able to travel home when his mother died and did not want a repeat of that situation.

The proceedings, begun by Mr Bates' lawyers this evening, are challenging the legality of his detention in quarantine.

Mr Justice Anthony Barr said it seemed a "novel" interpretation of the constitution to direct an inquiry into the lawfulness of a detention when that person is not currently detained.

Mr O'Higgins argued the procedure has "flexibility and simplicity".

He agreed with the judge that Mr Bates could seek a review of his situation after he arrives at Dublin Airport. But Mr O'Higgins said there was no guarantee such a review would be successful.

The judge said he saw the "human" nature of the application and recognised the tragic circumstances and the fact that Mr Bates needed to have the matter dealt with quickly.

He adjourned the case until 9am tomorrow.