A Fine Gael Private Member's Bill has proposed mandatory breath testing of drivers involved in serious road traffic accidents.
Transport spokeswoman Olivia Mitchell said that such tests were carried out elsewhere, and if one party feigned unconsciousness, it could be taken into account in any subsequent court case.
"Genuinely injured people can take the test later. The purpose is not to gather evidence for a court case or an insurance company. It is to get, collate, and be able to analyse the real causes of accidents in Ireland."
Introducing the Road Traffic Bill, Ms Mitchell said it was simply a guess to claim that speed and drinking were the main causes of road accidents.
"It is possible, and it is done in other countries, to get a very clear view of the relative importance of various factors in causing accidents and of their contribution to the severity of the accident. Speed, drinking, fatigue, driver-distraction such as mobile phones, road surfaces, lighting, and the vehicles themselves, are all potential contributors."
Ms Mitchell said that firm information was needed to inform public policy. "Otherwise, we are simply operating on guesswork and road safety is just too important to be left to anecdotal evidence."
She said the Bill also gave the Minister for Transport the power to make regulations, by order rather than statute, for the testing of substances other than alcohol, drugs or other intoxicants.
Minister for Transport Martin Cullen said the power to require a person to provide a breath sample, where a collision had taken place, already existed in the existing Acts.
He added that the Fine Gael proposal would result in a more confusing regime which would be more difficult to administer than the current provisions relating to breath testing at the scene of a road collision, which allowed for Garda discretion.
"I appreciate that deputies have been making inquiries in relation to the position with regard to breath testing at the scene of a collision in Northern Ireland and UK. My officials have examined this issue and the legal position here is in line with the practice in both Northern Ireland and the UK. In all cases, the taking of a breath sample at the scene of a collision is at the discretion of a police officer."
Mr Cullen said the existing Acts also placed an obligation on a person to provide a blood or urine sample in a hospital.
He added that the evidential testing in a Garda station for the presence of drugs was already provided for in the existing Acts. "The reason that there is no legislative provision to allow for preliminary roadside testing for drugs is that there is no available method for the taking of such a test."
Mr Cullen said that significant research relating to the matter had been, and continued to be, pursued. In the absence of any methodology for the taking of preliminary tests for drugs, it would be inappropriate to legislate for such tests, he added.
