The Chief Executive of the Road Safety Authority has said there has been a 21% drop in road deaths since July, compared to the same four-month period last year.
Noel Brett told the Dáil's Enterprise Committee that there have been 30 fewer deaths on the roads in the period.
He said it was much too early to say this was directly attributable to mandatory breath testing but that the figures were encouraging.
Speaking earlier on RTÉ Radio's Morning Ireland, Mr Brett strongly criticised comments from a councillor in Tipperary who said it was alright to drive after consuming 'three or four pints'.
Mr Brett said drinking and driving could never be justified.
In a local radio interview, Councillor Michael Fitzgerald also said it was wrong to arrest people if they failed a breath test the morning after.
Mr Fitzgerald, who was previously convicted of drink-driving, has since lost the party whip.
