Fine Gael's spokeswoman on health, Ms Olivia Mitchell, has called on the Government to delay the implementation of the ban on smoking in the workplace, expected to be in operation by the end of next February, because it has turned into a "lawyer's dream of legal loopholes".
She accused the Government of making "ham-fisted attempts" to ensure the smoking ban was legally watertight and said that while "time and thought now might delay implementation by a few months" such a delay would be "infinitely preferable to ten years spent defending the legislation in the courts".
Last week Mr Ahern expressed his confidence that the legal basis for the ban, having passed through the required European process, was rock solid.
He said legal advice had been received from the Office of the Attorney General that the Safety, Health and Welfare at Work Act 1989 might not encompass the banning of environmental tobacco smoke in the workplace.
It had been decided that primary legislation was required to remove this uncertainty, and the proposed Bill would provide for such amendments as were necessary to remove any legal uncertainties.
According to Ms Mitchell however the changes which are supposed to strengthen the legislation "in fact can only make it more prone to successful court challenge because the regulations, which have already gone to Brussels for the second time, were made under the original legislation."
Ms Mitchell is not alone in expressing here concerns about the legality of the legislation.
Last week the Irish Hospitality Industry Alliance insisted the smoking ban would not stand up to a legal challenge because of the status of most pub licences.
Mr Finbarr Murphy, an IHIA spokesman, said the vast majority of pubs had received their licences before 1902.
Such a licence covered the entire premises, including the place of dwelling. This meant that gardaí were free to search the public and private areas of the building in cases where people were found drinking after hours.
He said the Department of Health was now trying to distinguish between the public and private areas, so that the smoking ban could be enforced in the public area while the private area remained exempt.
However, the claim was dismissed by a spokeswoman for Minister for Health, Mr Martin.