So far this year, a number of whistleblowers have stepped into the public domain and made substantial allegations which have forced their way onto the political agenda.
Three in particular stand out: Sgt Maurice McCabe, Maíria Cahill, and now Gerry Ryan, the civil servant in the Department of Jobs, who passed a dossier to the Public Accounts Committee (PAC) alleging tax evasion by a number of former politicians.
When taken in the round, Sinn Féin’s attitude to each has been entirely inconsistent, with the party picking and choosing what it likes and discarding what it doesn’t.
Take the serious claims made by Sgt Maurice McCabe on the issue of the quashing of penalty points by An Garda Síochána.
One of the main battlegrounds in this controversy was the Public Accounts Committee (PAC), where Sgt McCabe wanted to give evidence, and wanted to do so in public before the committee.
A split opened up in the PAC on this, with some questioning why it was taking on this work, and secondly, asking whether Sgt McCabe should be given a public hearing.
Mary Lou McDonald, along with Shane Ross and PAC chairman John McGuinness, called firstly to allow Maurice McCabe a public hearing.
When it was decided by committee members that a private session was the better approach, Ms McDonald and Mr Ross asked whether a transcript of the meeting could be released afterwards.
At the time, PAC clerk Ted McEnery said no transcript could be published due to legal advice that Sgt McCabe had to be protected as much as possible.
Sgt McCabe has subsequently been vindicated but, at the time, what he was stating were still allegations.
Fast-forward to the recent allegations from Maíria Cahill that she was raped and subject to an IRA cover-up.
Between whistleblowers, there is a step-change in attitude by the party.
Under pressure, Sinn Féin adopted the bizarre stance where it said it accepted Ms Cahill was raped, but did not accept there was a cover-up.
It also said Ms Cahill’s allegations were being taken as “entirely true” by the media.
While Ms McDonald largely stayed off the airwaves as the controversy reached its peak, others stepped up to defend the party.
"When the annals of history are written about this period we are in right now, the question marks will not be so much for Sinn Féin or Gerry Adams as it is for Irish journalism, because we have reached a point where a whole cacophony of journalists have decided that somebody is entirely believable and entirely true in everything they say and other people are not," the party's justice spokesman Pádraig Mac Lochlainn said.
He added: “When somebody comes forward and makes allegations in any sphere of life, there is due process.”
When it was put that this was at odds with their attitude to Sgt McCabe, the Sinn Féin riposte was he had documentary evidence.
Yes he did, but maybe Sinn Féin could ask others in the republican movement whether there is any documentary evidence regarding what happened to Ms Cahill - or what people knew about it.
A number of weeks ago, another whistleblower emerged and Sinn Féin has again changed tack.
Gerry Ryan passed his dossier, which alleged a number of former politicians evaded tax, to the PAC.
Their names have been known to many in the media and politics since then, but could not be reported due to legal restrictions.
And yet, weeks later, but after the PAC received legal advice, Mary Lou McDonald stood up on Wednesday and said the following under Dáil privilege: "The whistleblower alleges Des O'Malley, Ray MacSharry, Gerard Collins, Máire Geoghegan Quinn, an S Barrett, Richie Ryan - a former minster for finance - and others… I am echoing the allegations that are very serious that have been brought forward by the whistleblower. That is the allegation, A Cheann Comhairle."
Those named by Ms McDonald deny the allegations.
The Ceann Comhairle, Seán Barrett, then told the Dáil: “I wish to state quite categorically, in case anybody is under any doubts when you say ‘S Barrett’, it does not apply to me.”
According to Mr Ryan himself, Michéal Martin - while minister in what was then the Department of Enterprise - referred his 763-page report detailing his allegations to the Revenue Commissioners, Garda Bureau of Fraud Investigation, the Office of the Director of Corporate Enforcement and the Mahon and Moriarty tribunals.
Mr Martin also referred the matter to Matthias Kelly QC, head of the UK bar council, who then carried out an independent report.
Richard Bruton, the current Minster for Jobs, referred a witness statement from Mr Ryan to the Garda Bureau of Fraud Investigation, albeit after a two-year delay.
Josephine Feehily, the head of the Revenue Commissioners, is also due before the PAC to discuss the Ansbacher issue on foot of Mr Ryan's dossier.
We do not know what action these developments may yet lead to, but perhaps Sinn Féin might let “due process” take its course with these allegations, too.
Ironically, Ms McDonald read the names from the Ryan dossier into the Dáil record on the same day her party whip asked the Ceann Comhairle if the Committee on Procedures and Privileges could investigate "an abuse of privilege by An Tánaiste and Leader of the Labour Party Joan Burton" last week.
Is it now the case that Sinn Féin decides which allegations it feels should be given due process, and which should not?