The AGSI described the proposal as an "emotional knee-jerk reaction"
A former chair of the Labour Court says gardaí should lose some of their pension rights if they go on strike.
John Horgan admits it is an unprecedented idea, but says it is something the Justice Minister France Fitzgerald should consider.
He says the move would reflect the "special and unique nature of police work" - but should come hand-in-hand with trade union status and access to the Labour Court.
It is part of a review of all Garda pay and conditions commissioned earlier this year, and published today.
He believes pension accrual should be denied, for a term of five years, to gardaí who do take part in industrial action.
He writes: "One of the unique features of the ‘contract’ under which Gardaí are employed is a very valuable pension scheme; it is even more favourable than the Civil Service. It recognises the special and unique nature of police work and it is, in my view, therefore appropriate that any member of [An Garda Síochana] who engages in industrial action should suffer an automatic reduction in his/her pension entitlement."
He acknowledges that it would be an 'unprecedented measure' and would face likely resistance from gardaí.
However, he argues: "I consider that it is a reasonable measure in the context that gardaí will have full negotiating rights and access to the Labour Court to resolve any differences they have with their employer."
He also stresses that it would be 'part and parcel of the uniqueness of' the force and would not apply to any other employment.
The AGSI has branded the pension proposal in the new report as an "emotional knee-jerk reaction to the threat by individual people to withdraw their labour", and suggested such a measure would be 'possibly illegal'.
Its president Antoinette Cunningham argued: “The main recommendation is around penalties for Gardaí if strike action is taken in the future. But surely, the framework to prevent threatened strike is what the report should have dealt with and not penalties based on the lack of clear industrial relations mechanisms.
"We expected a root and branch review but instead it seems this was a rushed report which failed to address the key elements of the terms of reference," she added.
The president of the Garda Representative Association (GRA) Ciaran O'Neill spoke to Newstalk Drive, and questioned the legality of the sanction.