A doctoral thesis on the CAB has also revealed it recovered €178.5m in taxes and €26m in seized assets over the same period.

Thesis author PJ Ryan, a law lecturer at Limerick Institute of Technology, said the CAB’s social welfare powers are an essential feature of its intention to tackle crime at the local and community levels.

The CAB initiated more than 600 actions against social welfare claimants in one seven-year period, as compared to 198 tax assessments in the same period.

Gardaí in Drogheda earlier this year stated their intention to target feuding drug trafficking gangs by going after their social welfare payments.

Its last annual report showed that, of the €5.6m CAB returned to the State last year, €323,000 came from social welfare overpayments.

A further €2.2m was seized as proceeds of crime and just over €3m was taken in taxes.

According to Mr Ryan’s thesis, between 1996 and 2006, CAB’s social welfare activities generated savings to the exchequer of €7,808,753 and received recovery payments of €4,066,136.

“Whilst considerably less than the financial income generated from forfeiture of assets it nonetheless represents a significant denial of cash flow to criminality from an area of the bureau that does not receive significant attention in wider academic or media discourse,” it said.