Garda whistleblower Sgt Maurice McCabe is to be interviewed by the senior counsel appointed by the Government to investigate his claims of malpractice within the force.

The terms of reference for the review to be carried out by Seán Guerin were published by the Government last night, and Mr Guerin will also be able to interview anyone else necessary.

However, Mr Guerin will not have the power to compel people to give evidence, but Government sources said co-operation with the review is expected.

Separately, Minister for Justice Alan Shatter sent an email to his Fine Gael colleagues thanking them for their support in recent weeks as he faced political pressure over the various Garda controversies.

Following his review, Mr Guerin will also report back to Taoiseach Enda Kenny in eight weeks with his conclusions, including whether a Commission of Investigation is needed into the allegations contained in a dossier Sgt McCabe gave to Fianna Fáil leader Michéal Martin.

Mr Guerin will "undertake a thorough examination of the action taken by An Garda Síochána pertaining to certain allegations of grave deficiencies in the investigation and prosecution of crimes" in Cavan and elsewhere made by Sgt Maurice McCabe, the terms of reference say.

As well as the dossier, which was given to Mr Kenny by Mr Martin, Mr Guerin will also examine a letter "understood" to have been sent by former confidential recipient Oliver Connolly to Sgt McCabe.

Mr Guerin will also interview Sgt McCabe, who has taken advice from former Tánaiste and Minister for Justice Michael McDowell, and any other relevant people, and will consider any relevant documentation provided by Sgt McCabe or anyone else.

Documents from the Garda Síochána, the Department of Justice and any other entity of public body as is deemed relevant”.

Mr Guerin will also examine “what steps, if any” have been taken by the Garda Síochána or other public bodies to “investigate and resolve” the allegations made by Sgt McCabe and will review the “adequacy” of any investigations carried out.

He will also consider if “there is a sufficient basis for concern as to whether all appropriate steps were taken by An Garda Síochána or any other relevant entity or public body to investigate and address the specified complaints”.

Mr Shatter’s email of thanks, sent to TDs and senators yesterday, said: “As you are aware, difficult issues have arisen in the Justice area over the last two and a half weeks.

“This is just a brief note to thank all my Fine Gael colleagues for your support in dealing with these issues and for the contributions that many of you have made in the Dáil, in statements issued and on the broadcast media. It is very much appreciated.”

He also thanked members of the Public Service Oversight and Petitions Committee “who raised important questions” when he was before the committee, and “those who spoke in the Dáil . . . and participated in what was an important debate on these issues”.

Meanwhile, the Public Accounts Committee (PAC) has been told it cannot publish a transcript of a private meeting it held where Sgt McCabe discussed the penalty points controversy.

Some member of the PAC, such as chairman John McGuinness, Independent TD Shane Ross and Sinn Fein’s Mary-Lou McDonald, as well as Sgt McCabe himself, wanted the transcript published.

The issue was referred to the Committee on Procedures and Privileges, which decides Dáil rules, but it has decided against publishing the transcript .

Sources said the view was taken than the contents of a private meeting should remain so but Mr McGuinness described the decision as “disappointing”.

The Terms of Reference for the Inquiry were agreed by the Government today, on the advice of the Attorney General.

They are as follows.

1. To conduct an independent review and undertake a thorough examination of the action taken by An Garda Síochána pertaining to certain allegations of grave deficiencies in the investigation and prosecution of crimes, in the County of Cavan and elsewhere, made by Sergeant Maurice McCabe as specified in:

a) the dossier compiled by Sgt Maurice McCabe and furnished to An Taoiseach on the 19th February 2014 and

b) the letter understood to be from Sgt Maurice McCabe to the Confidential Recipient, Mr. Oliver Connolly, dated 23rd January 2012 , part of which was furnished to An Taoiseach on the 21st day of February 2014.

2. To interview Sgt Maurice McCabe and any other such person as may be considered necessary and capable of providing relevant and material assistance to this Review in relation to the aforesaid allegations and to receive and consider any relevant documentation that may be provided by Sergeant McCabe or such other person.

3. To examine all documentation and data held by An Garda Síochána, the Department of Justice and Equality, and any other entity or public body as is deemed relevant to the allegations set out in the documents at 1(a) and (b) above.

4. To communicate with An Garda Síochána and any other relevant entity or public body in relation to any relevant documentation and information and to examine what steps, if any, have been taken by them, to investigate and resolve the allegations and complaints contained in the documentation referenced at 1(a) and (b) above.

5. To review the adequacy of any investigation or inquiry instigated by An Garda Síochána or any other relevant entity or public body into the incidents and events arising from the papers furnished at 1(a), 1(b) and 2 above.

6. To consider if, taking into account relevant criminal, civil and disciplinary aspects, there is a sufficient basis for concern as to whether all appropriate steps were taken by An Garda Síochána or any other relevant entity or public body to investigate and address the specified complaints.

7. To advise, arising from this review, what further measures, if any, are warranted in order to address public concerns including whether it is considered desirable in the public interest for the Government to establish a Commission of Investigation pursuant to the Commissions of Investigation Act 2004 and, if so, the matters to be investigated .

8. At the conclusion of the aforesaid review, within eight weeks of 27th February, 2014 or so soon as may be thereafter, to deliver a Report to An Taoiseach on the matters set out at 1, 5, 6, and 7 above.