There was a huge majority in favour of the party's successful candidates in the Northern Ireland assembly elections taking their seats.
The motion advocating the move, submitted by the party's ardchomhairle, involved a change to the party's constitution and required a majority of two-thirds plus one to be passed. After a lengthy debate, during which most speakers backed the motion, 331 of the 350 delegates eligible to vote supported it.
A motion from the McElchar/ McCaffrey cumann in Donegal, opposing participation by Sinn Fein in the assembly, was overwhelmingly defeated.
Proposing the party's involvement in the assembly, Mr Martin Ferris, from Kerry, a member of the ardchomhairle, said that, if adopted, Sinn Fein candidates could take on face-to-face those who wanted to hold on to power in the North and hold back the tide of change.
"I understand the reservations that republicans have about entering an assembly", he said. "But this is no Stormont. The partitionist set-up of the past cannot be applied any longer. This assembly's life-line is connected to the North-South bodies, the all-Ireland element without which it cannot function, and our intention is to expand that all-Ireland dimension. There are dangers in the steps we are taking. But we are no strangers to danger. There are challenges and risks for us, but the greater challenges and risks are for our opponents."
Mr Michael O'Brien, of the Portlaoise Martyrs cumann in Portlaoise prison, strongly supporting the ardchomhairle, said that the party should follow through on the logic, rationale and drive of the political strategy which had evolved from many years of struggle. "This strategy has been to confront those at every level who are opposed to self-determination for the Irish people. To stand aside at this juncture and allow no republican viewpoint to be heard, or implemented within the proposed all-Ireland structures, would be a negation of our responsibilities to those who have mandated us."
To loud applause, Mr O'Brien told delegates that he wished to share with them the experience of observing the return of six republican prisoners, four of whom were known as the "Balcombe Street men", from England to Portlaoise prison last week.
"You may ask what has this got to do with the proposed assembly. It is this: after 23 years in British prisons, these men are our own Mandelas. They are fit, they are strong, they are unbowed, unbroken, humorous, politically astute and aware, and they are full of honest opinion and integrity. And all of that comes on the back of trust, belief and, above all, unity during all those long 23 years in the belly of the beast.
"United, we can do whatever we want, just as those united POWS who have returned from England have endured and ultimately defeated the most barbaric prison system and conditions."
Mr Aengus O Snodaigh (Dublin) said he had always believed that too much faith had been placed by the leadership in the peace process and the ability of anti-republican parties, such as Fianna Fail and the SDLP, to deliver. "I believe that they will be quite content once an assembly is in place, and that they will seek to thwart any attempts by us to use it and the North-South bodies as stepping stones towards our goals."
While he remained suspicious of the process and the document, and while his faith in the leadership was not what it once was, he was a republican and he believed unity was strength, he said.
Mr Larry O'Toole (Dublin) said that the party should attend the assembly to keep socialist republicanism on the agenda. "We have a duty not to surrender hard-won and massive gains to the SDLP."
Mr Sean McManus, an ardchomhairle member, recalled that at the previous ardfheis he had found it difficult to advocate the party taking seats in the assembly. "But I also said that I could see no alternative, and since then, if anything, my position relating to the assembly has hardened. I see us taking seats in the assembly simply as a basis for strategic advancement of our struggle."
Mr McManus said that it would particularly suit the unionists if Sinn Fein did not participate in the assembly. "If we do not take a yes decision here today, we are reneging on the tens of thousands of people in the North, and in this State, who support us to articulate the republican viewpoint."
Supporting the party's involvement in the assembly, Mr Padraig Wilson (H-Block cumann) said that in many ways the struggle within the prisons was a microcosm of the overall struggle. "We had to bring to the system demands and scenarios which strategically and tactically were to our design and to our advantage in pursuing our objectives."
Ms Geraldine Ferrity (Magha berry prison cumann) said that she and her fellow prisoners believed the way forward was to back the motion allowing Sinn Fein representatives to take their assembly seats, if elected. "We have not taken the decision lightly. It is a unified decision."
