A judge has warned that anyone telling lies before the Garda whistleblower tribunal is wasting the money of hard-working people throughout the country.
In a hard-hitting opening statement at the Disclosures Tribunal, Supreme Court judge Peter Charleton said the public inquiry is being bankrolled by ordinary men and women through their taxes.
Any attempts to thwart its mission to establish the truth would be an unwelcome wasting of their money, he said.
"This tribunal is a drain on the resources of the Irish people and it is paid for by their submission to the democratic structures of which taxation has been a central part in our tradition," the judge said.
"Every lie told to this tribunal will be a waste of what ordinary men and women have paid for through their unremitting efforts.
"Every action of obfuscation, of diversion of focus and non-cooperation is unwelcome for that reason."
The Disclosures Tribunal will investigate allegations that Garda chiefs orchestrated a smear campaign, including false sex abuse claims, against whistleblower Sergeant Maurice McCabe, who exposed wrongdoing in the force.
The scandal brought the government close to collapse before the public inquiry was announced two weeks ago.
Judge Charleton, who heads the tribunal, said a "central concern" will be whether or not Garda top brass reacted to the outing of wrongdoing in the force with "thought-through malice whereby media briefings take place against individuals who rock the boat".
"As if that were not enough, there is an additional question as to whether those who air concerns about poor policing may also be targeted and attacked as to their family life and as to their adherence to basic standards of human decency," he said.
In his address at Dublin Castle, Judge Charleton confirmed the inquiry's terms of reference had been extended to include the role of the State child and family agency Tusla, relating to its file containing false allegations of sexual abuse.
It will also look at allegations of "inappropriate contacts" between the force and Tusla in relation to garda Keith Harrison and other whistleblower officers and investigate the role of the media in the scandal.
Superintendent Dave Taylor, former head of the Garda press office, made the allegation of a smear campaign against Mr McCabe in a protected disclosure last year.
"There are no preconceived notions in this tribunal as to who is a villain and who is a victim, if there are such, and it may be that what the tribunal finds will not be to everyone's taste," Judge Charleton said.
"The truth is bitter though it is not shameful."
Judge Charleton also appealed for witnesses with any knowledge relating to the investigation to contact the tribunal urgently. They have two weeks to get in touch.
An interim report is expected within three months.
Judge Charleton previously worked as senior counsel to the Morris Tribunal, which spent years examining corruption and negligence among some gardai in Donegal in the 1990s.