Timeline: Martin Callinan and the penalty points controversy

December 2012: Independent TDs Clare Daly, Mick Wallace, Joan Collins and Luke Flanagan call for an independent inquiry into allegation that thousands of fines and penalty points issued to motorists had been cancelled. In November a Sunday newspaper had carried reports of high profile individuals getting their penalty points cancelled.

The TDs say the internal investigation, in which Garda Commissioner Martin Callinan tasked Assistant Commissioner John O'Mahony with investigating claims that over 60,000 penalty points were incorrectly terminated by gardaí, was not sufficient.

May 2013: O’Mahony report published. Probe finds actions of the unnamed gardai may constitute a breach of Garda discipline rules. Callinan said: “I am relieved that no evidence has been found to suggest any criminality in the cancellation of fixed charge notices.”

September 2013: Comptroller and Auditor General report highlights significant loss of revenue to the State stemming from weaknesses in the fixed penalty system.

November 2013: Callinan seeks the return of documents from the Public Accounts Committee concerning the cancellation of penalty points. "I am of the view that these files containing personal data are files which I am responsible for and accordingly should be returned," the commissioner said in a letter to PAC chairman John McGuinness.

January 23rd, 2014: Callinan appears before the PAC. "Quite clearly here, we have two people out of a force of over 13,000 who are making extraordinary, serious allegations and there isn't a whisper anywhere else, from any other member of the Garda Síochána about this corruption, this malpractice and all of those things that are levelled against their fellow officers. Frankly I think it is quite disgusting, on a personal level I think it is quite disgusting."

January 30, 2014: Whistleblower Sgt Maurice McCabe gives evidence in private at the PAC about the cancellation of penalty points which the committee finds to be credible.

March 12th, 2014: Garda Inspectorate report into the operation of the points system finds "consistent and widespread breaches of policy" and a serious waste of money and resources. Garda whistleblower John Wilson says the report vindicates himself and Sgt Maurice McCabe. Callinan faces further calls to withdraw "disgusting" remarks.

The Commissioner releases a statement, saying: “I want to clarify that my use of that term was not in reference to the character of either Sgt McCabe or former Garda Wilson, but the manner in which personal and sensitive data was inappropriately appearing in the public domain without regard to due process and fair procedures.”

March 20th, 2014: Minister for Transport Leo Varadkar calls on Callinan to withdraw his comments. A number of Labour Ministers including Eamon Gilmore and Ruairí Quinn also say the Co0mmissioner should withdraw his remarks.

March 25th, 2014: Martin Callinan resigns. Noreen O’Sullivan takes over as acting Garda Commissioner.