Toireasa Ferris, one of a few Sinn Féin candidates to emerge from the recent local and European elections with their reputations undamaged, caused a bit of a stir last month when she made critical remarks about her party in An Phoblacht. Sinn Féin, she said, had fallen between two stools and was "neither a credible alternative to the government nor a party of protest". It was seen as a Northern-based irrelevance and meant "nothing to the bulk of people in the south". The party was suffering an identity crisis, she said.

On the face of it, there is nothing to get too excited about here. Fianna Fáil TDs are using much stronger language about their leaders currently, some of it on the record. But in Sinn Féin, dissident voices have rarely been treated kindly (he said euphemistically); rigid adherence to pre-prepared ideology was always the working method. Ferris's comments in An Phoblacht were a minor sensation, therefore, particularly as they came during a period when other members and councillors were leaving the party, in various states of dudgeon.

"The worst thing this party could do would be to circle the wagons and shy away from the debate we need to have," she wrote.

And she asked a question: "What are we trying to achieve in the 26 counties and what do we stand for, besides a united Ireland?"

Presumably there has been no shying away from debate in the wider Ferris family after the performance of Toireasa's father Martin in Roscommon on Wednesday. Ferris père, a TD for Kerry South, showed up at Castlerea prison to meet Pearse McAuley and Kevin Walsh, who had just completed their sentences for the murder of Garda Jerry McCabe in 1996. He immediately became involved in a car chase designed to keep the two killers away from the media and from a garda car with two armed detectives on board. In this he proved to be successful, although we can only guess what will be the long-term effect on the electorate of his low-rent gangsterism. In many ways, the car chase was pure comedy – more Jason Byrne than Jason Bourne – but the message was clear: Ferris, a poor man's Roger Casement, is still wedded to the old ways, to a kind of mucksavage republicanism which exists uncomfortably in a country where McAuley and Walsh will never be more than imbecile thugs, deserving of no public displays of support.

Toireasa Ferris has her own history with the McCabe killers, having refused repeatedly to condemn their action on The Late Late Show a few years ago, but her An Phoblacht remarks suggest that she has moved on from those days. Her father clearly hasn't. By his actions, he answers his daughter's question: Sinn Féin stands for speeding around country roads in the company of ruthless killers trying to avoid the guards. Brits Out, Up The 'Ra and They Haven't Gone Away, You Know.

There may be a tiny market in electoral support for this kind of outlook, but it is growing ever smaller. Sinn Féin is losing votes and seats as a result. Its message, in so far as it has one, is unclear and clouded by all the mystical four-green-fields nonsense which still has a hold on so many in the party. With the economy in crisis and the government widely derided, these should be the best of days for Sinn Féin in the south. Instead, it has conceded a whole swathe of left support to the Labour Party, to groups like People Before Profit and to individuals like Maureen O'Sullivan. Where it should be thriving, it is merely surviving.

This happens to all political parties from time to time, of course. The problem for Sinn Féin is that despite Toireasa Ferris's pleas, there has been no real sign of a debate in the party, one that helps the party define itself, in its own eyes and in the eyes of the public. Whatever you think about the Greens, they do love a good argument, regularly taking the opportunity to discuss policy and the role they should be playing in Irish life. We all know what they stand for, as a result, and we can agree or disagree as we choose.

The problem with Sinn Féin is that the absence of such a debate makes it impossible to detect what it might stand for or even to work out who are the modernisers and who are the Neanderthals. The Ferrises, in their own individual ways, have given us an insight in the last few weeks into what such a debate might look like. Toireasa is right, but for the moment it is people like her father who prevail.

Bertie ahern: The king of self- delusion

Former Taoiseach Bertie Ahern is still clinging to the myth that the country's current travails have nothing to do with him. He popped up on Newstalk the other morning and confirmed himself as the King Of Self-Delusion, blaming the collapse of Lehman Brothers for Ireland's difficulties and suggesting to presenter Claire Byrne that she wouldn't have a job if it wasn't for him. His new sports column in the News Of The World should be a laugh, therefore. In his current form, "How the Dubs rang rings around Kerry on Monday" seems like a possible topic for this weekend.