The Herald revealed yesterday that left-wing politicians Joe Higgins and Joan Collins were the latest TDs to admit to pumping constituency expenses into the their controversial campaign.
Socialist TD Clare Daly also revealed that she claims mileage from the Oireachtas in order to attend protests against the €100 charge.
But in a fresh twist today, Ms Collins indicated that she would have "no problem" repaying the expenses if an independent body found that she was breaking the rules.
The admission will prove incredibly embarrassing for Socialist TDs Clare Daly and Joe Higgins who are standing by the controversial claims.
The controversy has left the entire group in total disarray, with several members indicating that the use of expenses in this way amounts to a breach of Dail rules.
But Joan Collins' admission that she would repay the money, if an independent body found her claims to be in breach of the rules, will heap enormous pressure on Joe Higgins and Clare Daly.
"I am genuinely of the opinion that the travel expenses incurred in the course of my 'performance as a member of the Dail' are legitimate," she said, adding that she was elected on a platform against "double taxation".
"If it is clarified, not by government sources ... but by SIPO or an independent source, that the expenses should not be used for travelling expenses 'incurred in the performance of my duties as a member of the Dail', I would have no problem paying it back."
And the pressure on the three deputies has intensified after several members of their own group claimed that they do use the expenses system in this way.
Two members, Donegal TD Thomas Pringle and Waterford TD John Halligan, even suggested that the trio were in breach of Dail rules.
"I read the regulations. It's only for travel within a TD's constituency and for travel to and from the Dail. That's the wording of the regulations and that's my understanding of it," Deputy Pringle told the Herald.
Deputies Mick Wallace and Seamus Healy did not respond when contacted by this newspaper.
The issue was certain to be debated by the technical group at their weekly meeting today.
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