The jumper is a reference to a campaign against the 8th amendment.
Six TDs could be facing disciplinary action for breaches of the Dáil dress code.
The TDs from the Anti-Austerity Alliance-People Before Profit group could be sanctioned for wearing jumpers with the slogan 'Repeal', referring to the 8th amendment.
The disciplinary committee of the Dáil is now investigating whether the jumpers, worn in the chamber last month, were a breach of House rules.
Ruth Coppinger, Paul Murphy, Richard Boyd-Barrett, Gino Kenny, Mick Barry and Bríd Smith all wore the clothing during leaders' questions on September 27th.
The Citizens' Convention on abortion, which will hold its first public meeting on October 15th, was being discussed.
At the time, Fine Gael's Ciaran Cannon asked Ceann Comhairle Seán Ó Fearghaíl if Dáil rules were being broken - to which he replied: "Emblems of a party political nature should not be warn or otherwise displayed within the parliamentary precincts".
But Paul Murphy does not believe action is likely.