Timeline of events leading to review

May 16th, 2013: During a discussion on RTÉ's Primetime, then Minister for Justice Alan Shatter reveals that independent TD Mick Wallace was stopped for using his mobile phone while driving but avoided getting penalty points due to Garda discretion.

October, 2nd 2013: Mr Shatter criticises whistleblowers Sgt Maurice McCabe and former garda John Wilson in the Dáil, alleging they did not co-operate with the Garda investigations into their allegations that gardaí had corruptly terminated penalty points. The assertion is vigorously disputed by the whistleblowers.

January 23rd, 2014: The then Garda Commissioner Martin Callinan appears before the Public Accounts Committee (PAC) and says he finds the actions of the whistleblowers "quite disgusting". He says they are two people out of a force of over 13,000 "and there isn't a whisper anywhere else, from any other member of the Garda Síochána about this corruption, this malpractice".

February 9th, 2014: A story in The Sunday Times suggest there are concerns within the Garda Síochána Ombudsman Commission (GSOC) that its offices have been bugged. This comes after Mr Shatter announced that GSOC was to conduct a new inquiry into the penalty points allegations.

March 20th: The then Minister for Transport Leo Varadkar adds fuel to the controversy when he describes the actions of the whistleblowers as "distinguished" and calls on Mr Callinan to withdrawn his "disgusting" remark, which the Garda Commissioner had by then insisted was not a reference to the character of the whistleblowers. Mr Varadkar said: "There have been many words used to describe their actions. But if I was to use one word, the word I would use is 'distinguished."

March 25th: Mr Callinan announces his resignation. " I felt that recent developments were proving to be a distraction from the important work that is carried out by An Garda Síochána on a daily basis for the citizens of the State in an independent and impartial manner," he said. It soon emerges that the secretary general of the Department of Justice Brian Purcell visited Mr Callinan's home the night before the announcement.

March 26th: Mr Shatter apologises to the whistleblowers and concedes he misled the Dáil by saying they did not co-operate with Garda investigations. "It was never my intention to cause any upset and, if any upset was caused, I hope that my correcting the record of the Dáil today will put this matter to rest." However, pressure continues to mount on the Minister.

May 7th: Mr Shatter resigns as Minister for Justice following receipt of the report of Seán Guerin, a criminal barrister who had been asked to review the penalty points dossier supplied by the whistleblowers. The report was critical of the Department of Justice. Mr Shatter is quickly replaced as Minister for Justice by former children's minister Frances Fitzgerald.

May 13th: The Government resolves to initiate an expert review of the Department of Justice on foot of the Guerin report. Ms Fitzgerald declines to back Mr Purcell pending the outcome of the review.

May 28th: Mr Purcell appears before the Oireachtas justice committee, where he describes his visit to Mr Callinan's home the night before the former garda commissioner announced he was stepping down as "unusual". Asked if he regretted that the Department did not undertake and investigation into Sgt McCabe's claims, Mr Purcell replied that with "the benefit of hindsight...maybe we would have looked at it differently".

July 28th: The review of the Department of Justice is published.