In the absence of any new information emerging, it is difficult to see how the current controversy over alleged tax evasion by a number of former senior politicians will develop.

A number of former ministers have now been publicly identified in the Dáil as being the persons alleged by a serving civil servant to have been the beneficial owners of offshore Ansbacher accounts which facilitated the evasion of tax.

The civil servant who has made the claims, Gerry Ryan, was the authorised officer appointed under company law 15 years ago to investigate Ansbacher. He has maintained that information he uncovered was never adequately dealt with by various ministers and State agencies such as the Revenue Commissioners.

The former minister for enterprise Mary Harney has rejected claims made in the Dáil that she terminated Ryan's investigation in 2004 when she learned of some of the names emerging from his inquiries.

The former politicians who were named in the Dáil have denied ever having had an Ansbacher account.

The chairman of the Revenue Commissioners, Josephine Feehily, told the Public Accounts Committee that all material provided by Ryan had been examined and followed up. However she said that under confidentiality rules she could not show Ryan or anybody else individual tax files. She rejected any suggestion that there had been political influence brought to bear on the Revenue Commissioners.

She maintained that even before Ryan discovered information in 2003 and 2004 relating to an alleged secret ledger containing details of the accounts held by the senior politicians, Revenue had already established its “case base” on the Ansbacher issue and that his material did not add to this list.

So given that Revenue appears happy that all the money potentially outstanding from the Ansbacher scandal has virtually been collected by now and the conflicting charge and counter-charges that have been made , where to now for the allegations?

A number of politicians who have received the Ryan dossier have commented privately that the evidence set out may be considered legally to be hearsay.

In essence the claims are largely based on information provided by former bank officials who had access to the details of Ansbacher accounts held in a “black briefcase”and who related the identities of the alleged beneficial owners.

However the dossier given to committee members would appear to be a distillation of a far larger volume of material given, for example, to Micheál Martin when he was minister for enterprise and employment several years ago and more recently provided as a witness statement to the gardaí. When appendices are taken into account, this witness statement has about 5,000 pages.

Some committee members have asked privately whether the larger volume of material gathered by Ryan contains more supporting evidence to back up his claims.

However the legal advice to the committee is that it should not call Ryan to appear before it either publicly or in private, as it did with Garda whistleblower Maurice McCabe.

However there may be a way around this apparent obstacle. Under current rules when an individual is named at a hearing of the Public Accounts Committee, the person concerned must be sent a transcript of proceedings and invited to respond if they wish. In many cases those wishing to respond do so in writing. However some committee members have mused aloud as to what would happen if Mr Ryan, who was named in proceedings at the committee yesterday, opted to respond orally.