The question is whether Barry McElduff is a liability or an asset... Sinn Fein, which refuses even to acknowledge the IRA's responsibility for Kingsmill, clearly believes he is the latter
As in the case of former BBC NI contributor Jude Collins, the ex-MP's callousness towards the victims of violence is seen by many as a bridge too far. By Malachi O'Doherty
What are we to make of Barry McElduff? We can write him off as beyond consideration simply because he is a member of Sinn Fein, a defender of the good name of the Provisional IRA, a gang of politically motivated murderers who spilt more blood on Irish soil in recent decades than any other band of rogues or state body.
But there is nothing exceptional in that.
Politics works on the understanding that Sinn Fein is a democratically elected party with a right by virtue of numbers to govern this place when it eventually gets round to it.
The question over McElduff is more testing.
Acting the lig in a garage shop one night, he had himself filmed with a loaf of Kingsmill bread on his head.
This was on the anniversary of one of the dirtiest sectarian attacks in the history of the Troubles, in Kingsmill, an attack so shameful that the IRA still declines to accept responsibility for it.
The country was appalled by the joke. It didn't see anything funny in it.
Barry McElduff said he hadn't been thinking of the massacre at all. It was presumably the farthest thing from his mind. But that excuse was not believed by many, and even among some of those it wasn't much of an excuse anyway.
You'd think that if your political career had been founded on the defence of mass murder you might at least remember the murders themselves and which among them had to be treated with especial care, being those you denied your people having any part in.
My problem is this: if Barry McElduff was consciously sneering at the dead of the Kingsmill Massacre then he is beyond despicable. If he was laughing at the innocent dead - and others have! - then he deserves no credit or consolation, no place in our political environment, not a greeting nodded at him in the street or a breath of compassion or consideration.
Such a black insult against the most vulnerable, most wronged and most aggrieved among us would mark him out as worthless, past bothering with. He would have let himself down so low that he would be out of reach, beyond recovery.
But we have no way of knowing for sure that he offended as badly as that.
His defence is that he wasn't thinking about Kingsmill at all; it was all a horrible and unfortunate coincidence.
And that is possible.
If you believe in human decency, it is even a preferable explanation. Most of us would rather imagine that others do not sneer at the grieving and the dead.
Motivated to think well of our neighbours, we produced a peace process.
Even those who were attacked or had family and friends murdered said, in effect, that we should trust in the possibility of the killers being good and sincere people, even competent and conscientious politicians with the welfare of the whole population at heart.
It may have turned out that Northern Ireland had been so long out of politics that it really did only have a venal generation to pass the job onto, but that's another story; the people had faith that politics was possible even with former killers in office alongside baby barristers and the odd wideboy.
We have among us in our political parties and community groups, and in other circles, men and women who have murdered and justified murder and who still speak in justification and admiration of murderers.
They talk of horrific killings as incidents within an unfortunate conflict for which they had no responsibility, as if cutting innocent people to shreds with bomb blasts or knives was just something that had to happen.
And our experience as journalists or community workers or others who routinely meet former killers is that they are often indeed civil and decent people. Martin McGuinness won the genuine love and admiration of people he worked with, even though he might reasonably have expected to end his life in jail. David Ervine was a bomber and he held fast to the end to the ludicrous proposition that we were all to blame for what he did.
But one absolution for those with blood on their hands - or at least some of them - is that the evil they did was in the distant past, part of something they may have got caught up in.
Those who commemorate and revere the killers are of today and that is bad enough.
But to laugh at the dead, even now, years afterwards, never having accepted any moral responsibility for your defence of the gangs we call paramilitaries, that surely would remove a person from among any who wanted to be taken seriously as committed to change.
The line that McElduff appeared to cross led him into apparently sneering at victims.
The commentator Jude Collins also finds himself alienated after a tweet that distinguished victims who knew the danger they were in from those who didn't.
The example he cited was Patsy Gillespie, the human bomb, sent to be blown up in Coshquin Army base while his family was held hostage.
Jude Collins's insensitivity drew complaints and he now believes that he has been blacklisted by the BBC.
In social media discussion on this over the weekend he got little sympathy.
Patsy Gillespie might have known he was a "legitimate target" in the eyes of the IRA, but that consideration has no moral value at all unless you accord to the IRA the right to kill some people, if not others. If anything, it only attributes courage to Mr Gillespie.
Not knowing for sure whether Barry McElduff's joke was what it appeared to be puts us in a difficult position.
Was it a gauche stumble into concerns he should have thought through, or was it even perhaps a black joke leaking out from his unconscious without the censoring filter of common sense?
We don't know.
And we don't like not knowing, so we either damn him as evil and twisted and want to exile him from political life or we want to allow that he's an affable bloke who meant no harm and give up trying to work it out.
But the calculation a political party will make about a member will be a bit different. It sees that the outrage is coming from people who don't vote for it anyway.
And the endorsement comes from some who like his cheek and who don't agonise about past massacres.
The question there is primarily whether the man is a liability or an asset.
Sinn Fein has decided that Barry McElduff is an asset.