The Garda Representative Association has said its members have stepped up their non-cooperation in protest at proposed pay cuts.
It confirmed that some members have started to "use their discretion" in relation to pursuing what they called revenue-gathering offences including those involving motor tax.
GRA President John Parker said they are also considering their continued participation in the transformation agenda for the first Croke Park Agreement.
GRA members have refused to use their personal phones and laptops for the past two weeks.
Last weekend, members did not volunteer to police a GAA match at Croke Park, which meant that gardaí had to be redeployed from normal duties.
Asked about concessions for other frontline workers including prison officers and firefighters, Mr Parker said there was a campaign to divide and conquer.
He noted that while those groups had been offered concessions, they had not yet been accepted.
He said that signing up to the Croke Park proposals would mean giving the Government a blank cheque to make further cuts to allowances.
Meanwhile, the National Ambulance Service Representative Association (NASRA) said that from 15 March, it was withdrawing goodwill, including use of personal phones, computers, satellite navigation systems.
Its 500 members will also refuse non-rostered duty at public events.
NASRA members make up almost one third of all the paramedics working for the HSE ambulance service.
Secretary Tony Gregg said ambulance paramedics used a mapping system provided by the HSE to respond to emergencies but also relied heavily on their personal sat navs.
He said withdrawal of goodwill was only the first phase of their scheduled protest.
He said the protest would continues until the Government realised the full extent of the changes that have already been accepted and implemented in the first Croke Park agreement.
'No renegotiation' of Croke Park
Earlier, Government sources ruled out any prospect of revisiting or renegotiating the Croke Park proposals.
The deal is aimed at cutting an extra €1bn from the State payroll bill over the next three years.
SIPTU President Jack O'Connor appealed to the Government to reach out to unions who pulled out of the Croke Park agreement talks.
However, management sources insist that those who do not back the agreement cannot expect to benefit from its protections.
In the week since the Croke Park proposals were hammered out, unions who stuck with the talks to the bitter end have been deciding how to advise members on a ballot.
However, some unions walked out and remain outside.
Concessions for 24/7 frontline workers who remained in the talks have infuriated others, including nurses and gardaí.
Government sources said it was inaccurate to describe letters of clarification on concessions for prison officers and firefighters as "sweeteners".
However, they noted that unions who stayed in negotiation were able to mitigate the impact of management's proposals.
They added that the Government considers that any party that chooses to remain outside the provisions of the agreement or that opposes its implementation cannot expect to benefit from it.
Public servants 'better off with one agreement'
Speaking on RTÉ's Morning Ireland, Mr O'Connor said that public servants are better off with one agreement.
He said an effort should be made to see if anything can be done to address the most serious concerns of people outside of the agreement and to create the basis for a better agreement all round.
He added: "I'm not sure the proposal, as it stands, is adequate. But I am sure that everyone who works in the public service is better off with an agreement.
"That's why I supported the Croke Park Agreement when it was going down in flames."
He said that any Government plans to implement a pay cut across the board for all public servants would be "monumentally stupid".
The new agreement includes pay cuts for top earners, additional hours for no extra pay, and reductions in allowances and premium payments.
Minister for Transport Leo Varadkar said it was never the desire of the Government to divide or split the unions or to have unions left out of the process.
He said he did not know if it was too late to bring them into the tent or not and that it was an issue for Minister for Public Expenditure Brendan Howlin.
ACHPS members in motion over ICTU membership
Senior civil servants in the Department of Foreign Affairs belonging to the Association of Higher Civil and Public Servants have passed a motion calling on the union to leave the Irish Congress of Trade Unions.
In a letter to members, Chairman of the Department's branch of the AHCPS Peadar Carpenter described the Croke Park proposals as "grossly unfair and totally unbalanced".
Under the proposals, all members of the AHCPS would be subject to pay cuts of at least 5.5% applied to those earning over €65,000 as well as a three year increment freeze.
The union is recommending rejection.
Mr Carpenter's letter states that it is incredible that virtually all the savings on pay in the civil service must only come from those earning over €65,000.
He noted that senior civil servants are also struggling with mortgages and financial commitments.
Mr Carpenter said that he has come to the conclusion that a decision was made by some representatives of Government and some union leaders that a deal was needed at any cost - and that the deal was structured to ensure that enough unions with the requisite votes would be in a position to vote in favour.
He said that senior grades had been "shafted" - adding that there may be a need for a union to represent all senior grades across the public service.
The branch's motion to leave Congress will be discussed at the AHCPS Annual Delegate Conference in May.