Agriculture Minister Dara Calleary resigned in the wake of the dinner.
Gardaí are investigating possible breaches of Covid-19 guidelines at a an Oireachtas dinner in Galway on Wednesday night.
Former Agriculture Minister Dara Calleary has resigned after attending the event at a hotel in Clifden.
The Taoiseach has accepted his resignation and says it was an error in judgement.
Meanwhile Fine Gael Senator Jerry Buttimer, who also attended the event, has resigned as Leas-Cathaoirleach of the Seanad.
Gardaí said: "An Garda Síochána is investigating an event that was held in Co. Galway on the 19th August, 2020 into alleged breaches of The Health Act 1947 (Section 31A-Temporary Restrictions) (COVID-19) (No.3) Regulations 2020, as amended.
"As this is an active investigation An Garda Síochána has no further comment."
Speaking to MidWest Radio, Mr. Calleary says he didn't expect over 80 people to be there.
''We were told that done in accordance with the guidelines that they had got'', he said.
''The tables were very well spaced out, the room was very well spaced out there were two rooms effectively.
''Certainly I didn't expect there to be 80 at the end of the day, I should've had the cop on not to have gone''.
