A recurring question in politics north and south is the role which Gerry Adams played in the death of Jean McConville and in the whole question of 'the Disappeared'.
Another question, which Adams has not convincingly answered, was his alleged membership of the Provisional IRA, and also to what extent he informed the authorities quickly enough about his brother Liam's sexual abuse of his own daughter.
These questions will assume an even greater prominence this week, during which the BBC is showing an in-depth documentary on the Disappeared, and also when his brother is due to be sentenced.
At times, the media questioning of the Sinn Fein leader has been intense, and notably so by Miriam O'Callaghan in an RTE programme, when Adams assumed the role of a media 'victim'. In reality, he is a skilled performer who can use words in a way which his listeners often find hard to interpret. Indeed, he gives the impression of a man who cannot understand why others might have difficulty with what he has to say.
Perhaps he is genuinely in denial over certain issues and believes that he has cleared up all the doubts, or he simply does not wish to add more detail to answers he has already given.
That is his prerogative, but he cannot assume that people will believe that he has answered their questions in the way that they felt entitled to expect.
There are some specific allegations about his role in the Disappeared from former close colleagues, which demand a clearer answer than Mr Adams has been prepared to give so far. There are also serious questions still unanswered about the time he took to come forward on the child sex abuse by his brother.
Over the years Gerry Adams has been a high-profile leader of Sinn Fein who has shown the ability to emerge with less damage than others from sustained and justifiable questioning.
Yet he now faces accusations from other senior politicians that his credibility lies "in tatters".
The key quality for any leader is credibility, and the time has come for Mr Adams to ask himself if he really is the right person to lead the republican movement. This week may be the time when he finally asks himself not only does he want to carry on, but is he really fit to do so. We believe that it is time for him to go.