The Labour Party has warned Fine Gael to brace for a bitter Coalition row if they make Attorney General Marie Whelan the scapegoat for the damaging findings in the Fennelly Commission.
Ms Whelan has come under intense scrutiny since the publication of the report into the events leading up to former Garda Commissioner Marin Callinan's shock retirement.
And she faces the prospect of an unprecedented vote of no confidence in the Dáil if a Sinn Féin motion is successful.
Coalition sources last night insisted it was not constitutionally possible to hold such a vote.
Nonetheless, Sinn Féin deputy leader Mary Lou McDonald said that the motion has been received by Chief Whip Paul Kehoe and they will press for it to be accepted.
Taoiseach Enda Kenny and Tánaiste Joan Burton both insist they still have confidence in Ms Whelan despite the damning findings of the report.
Senior Labour figures said that any wavering of support from the Fine Gael camp would have serious consequences for the Coalition.
There was concern yesterday in the junior Government party that Ms Whelan, a Labour appointee, may even be forced to take the fall over the controversy.
However, Labour Party sources said a clear signal will be sent to Fine Gael not to throw Ms Whelan "under the bus" over the findings in Justice Nial Fennelly's report.
"With the heat on Enda, they will inevitably look to throw someone else under the bus. If they try that with the AG, then there will be Coalition tensions," a senior Labour source told the Irish Independent.
Ms Whelan was criticised for her failure to contact either Mr Callinan or former Justice Minister Alan Shatter about the potential legal landmine stemming from the widespread recording of certain telephone calls in garda stations.
She claimed she did not contact Mr Shatter because he was "part of the narrative" and there were allegations relating to him personally.
A source close to Mr Shatter said the former minister was "very disappointed" by the evidence of Ms Whelan - who he worked closely with during his time in Cabinet.
"I don't know what was going on in her head," said one source. "Why she didn't contact him about the recordings during that weekend is a mystery to me," the source added.
Ms Whelan also drastically changed her evidence relating to the legality of the secret recordings and was forced to apologise to the commission for her "trenchant language".
While Sinn Féin has tabled a motion of no confidence in the AG, Mr Kenny is also facing a vote on his ability to lead the country. He is also likely to face further questions over evidence he gave the Fennelly Commission.
Fianna Fáil leader Micheál Martin accused the Taoiseach of spinning the findings - and has called on him to resign.
Mr Martin described as "very callous" Mr Kenny's decision not to allow the former Garda Commissioner to wait a couple of months before stepping down.
Sinn Féin leader Gerry Adams said "no amount of spin" could hide how dysfunctional the Government had become.
However, the Tánaiste weighed in firmly behind the Taoiseach on the matter.
And the only member of Cabinet to accuse Mr Kenny of sacking Mr Callinan also said he accepts the findings of the Fennelly Commission.
Communications Minister Alex White had publicly criticised Mr Kenny's handling of the former commissioner's retirement at the height of the garda scandals last year.
However, yesterday he said: "My view is that both the Dáil and the Seanad agreed that the issue should be dealt with by an independent commission and Nial Fennelly was then appointed.
"He has now reported and we should accept his conclusions, as I do." Health Minster Leo Varadkar said that the report "debunked" suggestions that Mr Kenny had sacked Mr Callinan.
Social Democrat TD Catherine Murphy has said the disposal of personal papers and disappearance of a SIM card belonging to the ex-Garda Commissioner Martin Callinan is one of the "key reasons" for the Dáil to be recalled.