A senior counsel has been appointed to investigate allegations of wrongdoing at the Oireachtas banking inquiry.

Senan Allen has been asked by the clerk of the Dáil, Peter Finnegan, to examine the claims about the committee's investigation team by a whistleblower who had worked with the committee.

The whistleblower alleged there were potential conflicts of interest within the investigation team and also claimed preferential treatment was given to some key witnesses.

Mr Allen will have to compile his report on the series of claims and submit it by the end of next month. The terms of reference are to be drafted over the coming days and released by the end of the week.

In a letter to members last week, the former investigator said their salary had been stopped since the claims came to light. However, the Houses of the Oireachtas yesterday denied this and said no employee was taken off payroll.

It said it does not comment on individuals but said it has acted within the law at all times.

The House said it “strongly refutes” any claim it has acted illegally and insisted it adhered to the Protected Disclosures Act at all times.

The whistleblower has submitted an 82-page document under the Protected Disclosures Act. It alleges preferential treatment was given to the Central Bank and the Department of Finance.