The Public Accounts Committee has agreed to invite a serving garda whistleblower to appear before it in a private meeting on Thursday.

It is understood that members heard legal advice that the whistleblower cannot name names and will be restricted in what he can say and what he can be asked.

They also heard that there were legal concerns about the completeness of the information, but members were told that a hearing with the whistleblower was a political decision.

It is believed that Fine Gael members had reservations about bringing in the whistleblower, while Labour members expressed concern at the limited information they could obtain if they went ahead with the hearing.

A motion was put down to have a vote on the matter by independent TD Shane Ross and Sinn Féin's Mary Lou McDonald.

However, Fine Gael's Kieran O'Donnell asked for an adjournment so they could reach a consensus and avoid a vote.

During the adjournment, Labour members decided the best course of action was to bring the whistleblower in on Thursday as planned.

After the adjournment a consensus was reached and a vote was avoided.

It was decided to invite Sergeant Maurice McCabe in on Thursday in a private session. It will be held at 2pm.

Sgt McCabe will be restricted to speaking on the Comptroller and Auditor General's report on penalty points.

PAC Chairman John McGuinness said: "While the minister has intervened and the matter is now with the Garda Síochána Ombudsman Commission, that investigation will not overlap with the examination by the PAC of the report of the C&AG.

"The PAC is looking at systems processes and procedures used in the management of the fixed charge notice system and whether possible weaknesses in systems and in controls could potentially have led to a loss to the Exchequer.

"The Garda Ombudsman will investigate the allegations of multiple incidents of wrongful cancellations which are outside the remit of the Committee."

Ms McDonald welcomed the decision to invite the whistleblower to address the committee.

She said: "While it would have been my strong preference to invite the individual to appear before the committee in public session, I defer to the result of the committee vote."

She added: "I have expressed my belief that it is important that the whistleblowers are afforded the opportunity to give evidence.

"I welcome that this opportunity has now been presented."

Gardaí had no comment on tonight's development.

Earlier, another garda whistleblower, John Wilson, said he is anxious to appear before the PAC in order to rebut some of the claims made by Garda Commissioner Martin Callinan last week.

He said he attended the hearings last Thursday and "as a result of some of the evidence that Mr Callinan gave to the PAC, I am anxious to rebut some of the allegations that he made".

The retired garda gave a guarded welcome to Minister for Justice Alan Shatter's decision to refer the investigation to the Garda Siochána Ombudsman Commission.

However, Mr Wilson said he believes there should be two parallel investigations, one by the PAC and one by the Garda Síochána Ombudsman Commission (GSOC), into the penalty points controversy

Speaking on RTÉ's Today with Sean O'Rourke, he said he believes the matter should have been independently investigated several months ago.

"As I have stated publicly before, in my opinion humble as it may be, if some independent person examined this matter it wouldn't take them too long to come to the same conclusions that both myself and Sergeant [Maurice] McCabe came to," he said.

Mr Wilson estimated that the cancellation of points has cost the Exchequer up to €8m.

He said the GSOC investigation will only work if full and unrestricted access to the garda computer system PULSE is given.

He described the situation as a scandal, but said he believes that if it is properly investigated that the truth will come out.

Meanwhile, Taoiseach Enda Kenny told the Dáil the Minister for Justice acted appropriately and decisively in referring the controversy to GSOC.

Mr Kenny was responding to a question from Sinn Féin President Gerry Adams, who he said used to have a very different way of dealing with whistleblowers.

Mr Adams asked the Taoiseach why the minister was referring the matter to GSOC when the matter emerged two years ago.

He also asked if GSOC would have the power to question Commissioner Callinan.

Earlier, Tánaiste Eamon Gilmore said it is important the penalty points controversy is investigated and that the reputation of the gardaí is upheld.

Speaking on his way into Cabinet, he welcomed the move to allow the commission to investigate the allegations. 

Minister for Public Expenditure and Reform Brendan Howlin said he hoped the investigation would establish the truth.

He also expressed concern about the conduct of the Public Accounts Committee.

He said he was "personally concerned" at some members of the committee giving a daily assessment on the media.

Minister Howlin said the Oireachtas has to prove to the people that inquiries can be conducted in a fair and impartial way. 

GSOC to seek access to garda computer system

The Garda Siochána Ombudsman Commission said it will seek access to the PULSE system and broaden the investigation into the penalty points system if necessary.

Speaking on RTÉ's Morning Ireland, commission member Kieran FitzGerald said they expected to start work as soon as they received formal notice of Minister Shatter's referral.

He said: "The political controversy and various media coverage is not conducive to good public confidence in either the oversight system or the system of justice, so we would start work immediately.

"In fact, we're preparing already in anticipation of getting this referral."

Mr FitzGerald said he expected it to be a very wide-ranging investigation.

Public confidence in gardaí must be maintained

Mr Shatter rejected suggestions that he is trying to silence anybody in relation to the penalty points controversy.

Speaking on RTÉ's Morning Ireland, Mr Shatter said there was no capacity within the PAC to deal with this matter adequately.

He said the committee members were being confronted by allegations made by a serving and former member of the force against current members and there was no facility for existing members of the force to respond to those allegations.

Mr Shatter said the situation was also a major distraction for senior management in the force, who have an important role to play in ensuring the protection of the general public in the investigation of crime.

He said it was crucial that public confidence in gardaí be maintained.

Asked why he did not refer the issue to the GSOC earlier, Mr Shatter said he could not because it would have been an abuse of legislation that prohibited the ombudsman from investigating in a situation where a serving member of the force makes a complaint.

Mr Shatter said it was completely undesirable to have gardaí engaged in political controversy.

He said the vast majority of PAC members went about their business in a very considered and appropriate way, but there was a minority of members who were prejudging issues that had come before it.

The minister said: "I think it's important for the Public Accounts Committee themselves to determine how they now proceed.

"I would hope that whatever information and documentation is being furnished to them will be furnished to the Garda Ombudsman Commission."