THE economist who chaired the 'An Bord Snip' group has said the Seanad wastes time and money because senators "gasbag on", and it should be abolished.
Colm McCarthy, who wrote the report for the last government, which recommended €5.3bn in cuts, also said keeping the Seanad would be like buying two "banger" cars in case one broke down.
"I don't see the case for it," he told the Irish Independent.
It comes as the campaign gets into gear this week, with Fine Gael launching its push for a Yes vote and other groups ramping up their campaigns.
A number of senators, including Labour's John Whelan and John Kelly, are set to campaign with the anti-abolition Democracy Matters group this week.
Mr McCarthy also backed up the disputed cost figures used by the Yes campaign, which claims scrapping the Upper House would save €20m.
He said the Oireachtas told his 'Bord Snip' group in 2009 that getting rid of the Seanad would save €24.5m, and he said that cost would have fallen since then because of cuts to public sector and politicians' pay.
"The cost of it would have come down a bit since then," Mr McCarthy said.
He also said there was a massive hidden cost in the amount of time ministers had to spend in the Seanad, steering through legislation and taking questions.
"They have to spend a couple of hours in there listening to the lads gasbag on," he said.
He rejected the idea that the Seanad acts as a safeguard for the Dail, saying the Dail should be well able to do that itself.