For reporters based in Leinster House, a routine assignment is to find out what happened at the weekly parliamentary party meetings. These are meetings of TDs and Senators, which are supposed to be private. They are anything but. The upshot is every juicy detail (and it usually involves copious whingeing) finds its way into print.

There is one exception. Sinn Féin holds a weekly meeting involving not only its 17 TDs and Senators but also its 60 or so staff in Leinster House. Yet, nothing escapes. Not enough for a haiku, let alone a 500- word report. It is all hermetically sealed.

“That’s a source of pride to us,” says Seán Mac Brádaigh, party leader Gerry Adams’s official spokesman. “We see it as a good way to behave as a political party. It will make us effective.”

Party apart

It bolsters the image of Sinn Féin as a party apart. Its representatives and officials stick together – they congregate in one corner of the Leinster House canteen – and don’t really socialise with people from other parties. Only one of its parliamentarians, the affable Waterford Senator David Cullinane, goes into the members’ bar.

For Sinn Féin, that front is a testament to its discipline. For its opponents, it is the uniform, blind and slavish characteristic of a cult. And so they view Sinn Féin with a mixture of contempt and envy. A senior Fianna Fáil strategist believes the party now needs Sinn Féin's discipline and central command if it is to have any chance.

Until recently, any account of Sinn Féin would have included the two words “inevitable rise”. The support graph is going up, but such analysis assumes no change. The two recent examples of the Dublin South West byelection and the extraordinary disclosures of Maíria Cahill have introduced uncertainty for the first time.

So where is Sinn Féin at in the South? What is its overarching vision? Is it different from the North? What is its strategy? Where are its policies? Who are its driving forces? And what are the things that can potentially trip it up?

In terms of vision, there are two central concepts that divide North and South for Sinn Féin. One is a united Ireland. And the second? Says Mac Brádaigh: “We want a citizen-centred society with strong public services and a progressive tax system, where the vulnerable are protected.”

Internal change

How they are manifested is very different either side of the Border. In Dublin, the North is seldom mentioned. The party has focused on domestic politics, particularly grassroots protests against Government policy. Gradually, it has moved away from a reactionary stance where it opposed everything, to developing either its own alternative policies or mellowing its stance. On Europe, it has moved from being Eurosceptic to being Eurocritical. Dublin councillor Eoin Ó Broin has pushed for a position of seeking internal change in the EU, away from market-driven policies and “aggressive internationalist agendas”, as he put it, to being a more egalitarian entity.

Likewise, if you track its economic policies over the years you see some measures being dropped, such as a 17.5 per cent corporation tax rate, and others being “parked”, such as wealth tax.

Water charges

That was illustrated in the recent byelections, where water charges wasn’t a red- line issue and then became one (which backfooted the party). Mac Brádaigh and Ó Broin say the internal debate in the party hadn’t concluded when the election was called and it got caught in a bind.

If the party began in 2011 opposing everything and going for the populist line, it has changed subtly. For example, it will not say to people not to pay water charges.

It is clear the party does not want to be caught in the same situation as Labour was in 2011, going into government with promises it knows it can't fulfil.

For Ó Broin, that brings up the question of when. For him, the party needs another election cycle before it can go into a coalition. Mac Brádaigh speaks of a cumann in every parish in the country. There is a bit of Fianna Fáil 1926 to all of this, but it is clear there is a sense – though it hasn’t been agreed – that Sinn Féin, if it waits one more election, can be either the biggest or second biggest party by, say, 2021.

But there are significant drags, not least the legacy issue brought up by Maíria Cahill’s allegations. Without doubt, it has set the party back. A senior Labour figure said it was the first time he had seen Mary Lou McDonald flailing.

For opponents, like the Fianna Fáil strategist, it has damaged McDonald badly. “The mask slipped a little. For non-core Sinn Féin supporters, people who thought they were making sense, especially Mary Lou, this has put them off voting for Sinn Féin.”

Will a succession of such incidents damage Gerry Adams and his party? An experienced Fine Gael Senator says the Cahill allegations won't be the overriding issue in the next election. "The narrative will be the economy and Sinn Féin's policies are still weak. That's what we need to concentrate on." For his Labour counterpart, growth in the economy – and the mood of the electorate – will determine everything.

How will Sinn Féin deal with it. Ó Broin and Mac Brádaigh frame the party response in terms of an all-encompassing truth and reconciliation commission (a cop-out, say opponents). Senator Kathryn Reilly says that for somebody who was not a core Sinn Féin supporter, the legacy issues "might be an issue for them in terms of supporting the party".

Secrecy

With the Cahill affair has cropped up criticisms that the party is still arranged with the secrecy, order and discipline of the Provisionals. There are also arguments that Sinn Féin is a kind of cult where everybody slavishly follows Gerry Adams.

“We value discipline,” says Mac Brádaigh. “We do thrash things out internally ... It is seen as a republican virtue that once they are thrashed out internally we will agree that that is the party line and that is what we will promote. We cannot understand that what has been seen as a virtue is seen as a flaw.”

Much has been made of the succession . For the party, it’s a non-issue. “Without a shadow of a doubt Gerry will lead us into the next election,” says Mac Brádaigh. Sinn Féin’s party hierarchy: the main players The prime strategic body for Sinn Féin in the South is the 26 County Directorate. This deals with all the party’s political strategy, policy development and organisation. The body includes three of the party’s most senior politicians: Gerry Adams, Mary Lou McDonald and Pearse Doherty. The other members are:

Ken O’Connell: The chairman, political director O’Connell is an experienced backroom strategist and organiser in the South who maintains a low profile. His only foray into electoral politics was when he stood for the party in Wicklow in the 1992 general election. He finished well down the field. He spent over a decade based in Cork as Munster organiser, before becoming political director. Typical quote: “We now need to use these resources to systematically and scientifically build political strength.”

Trevor O Clochartaigh: A recent convert to Sinn Féin. Former member of Labour and an independent, this native Irish speaker from Carna in Connemara has an eclectic background. He was a leading figure in student drama at NUIG and was latterly a TV director, directing Ros na Rún on TG4 and Fair City on RTÉ. Rarely speaks about the North.

Ciarán Quinn: Another very experienced and senior strategist, he has been an adviser to both Adams and McGuinness. The Belfast native has been involved in southern politics on-and-off for 10 years but moved down full time after the 2011 elections. His job is to articulate the part’s overall position and control a large press office, that is now operating north and south, in the regions and in Europe.

Dawn Doyle: A senior figure for the party in the South for almost two decades, the Wexford native has long experience of media relations, being press officer and director of publicity since taking up her current role as general secretary in 2009.

Stephen McGlade: The Leinster House manager spent the early part of his career in Belfast and was involved with the party’s youth wing. He was a special adviser to Conor Murphy before moving to Dublin in recent years.

Joanne Spain: An economics graduate from TCD, the Dubliner has been the person most responsible for shaping and professionalising the party's approach to its finance policies in recent years. She has stood for the party in the past, most recently in the general election in 2007 in Dublin Mid West, where she suffered the fate of many other party hopefuls. She is the party's economic adviser in Leinster House and was formerly a political director for the South.

Other key advisers in the South are: Seán Mac Brádaigh: The Dubliner recently became Gerry Adams's main spokesman after a period as the party's director of publicity. He is the main writer for most of Adams' main speeches, including his Ard Fheis addresses. He was a journalist with An Phoblacht and edited it for five years until 2010.

Eoin O Broin: A councillor in Clondalkin and likely to be elected into the Dáil in the next election. Educated at Blackrock College and UCD, he has been involved with Sinn Féin for 20 years. He spent a decade in the North and was a councillor in North Belfast. His influence cannot be understated. Sinéad Ní Bhroin: She is the sister of Eoin O Broin and was previously involved with the Greens and small left-wing parties before joining Sinn Féin. She worked in the press office but in recent years has been main adviser to Mary Lou McDonald, and latterly Peadar Tóibín. Shannon Brooke Murphy: She recently succeeded Ní Bhroin as adviser to Mary Lou McDonald. From Canada, Murphy has been a prominent Sinn Féin activist and is a human rights lawyer with postgraduate degrees from NUI Galway and Middlesex University.