Why the McCabes want a public inquiry
Garda whistleblower Sergeant Maurice McCabe wants a public inquiry into the alleged smear campaign against him, not the commission of investigation proposed by the government.
Such a process would allow witnesses to be called and evidence to be heard in public similar to the tribunals of inquiry, like the Mahon Tribunal which looked into former Taoiseach Bertie Ahern's finances.
In last night's statement from Mr McCabe and his wife Lorraine, they say they want to make it clear that they don't want truth and justice "postponed" by a commission of investigation.
Such a probe "can conduct a secret investigation behind closed doors and make a report, into which we have no input as of right, in nine or 18 months' time," they said.
"We are entitled to the truth - justice can follow in its wake," the statement said.
They refer to the recent O'Higgins Commission, which was held behind closed doors and said the experience was "too fresh in our minds to allow for a repetition."
The statement says because the process was held in private, the public were not given an insight into Sgt McCabe's experience.
It follows reports - that have since been denied - that Garda Commissioner Nóirín O'Sullivan directed her legal team to discredit Sgt McCabe.
Commissions of investigation are supposed to be less expensive and a speedier method of probing matters of public concern than a tribunal of inquiry.
Under the legislation, a tribunal of inquiry can still be set up after a commission has reported.
Previous commissions of investigation include the examination of the 1974 Dublin and Monaghan Bombings and the investigation into the banking sector after the crash.
Such commissions are required to seek the voluntary cooperation of witnesses but can compel people to give evidence if necessary.
They also have powers to search premises and take documents but are intended to be less adversarial than tribunals. The evidence given in such commissions is private and this is one of the main points of contention for the McCabes.
Fianna Fáil, Sinn Féin and Labour have all backed their call for a public inquiry.