Niall Collins was, on balance, correct in apologising for a letter he sent on behalf of a convicted drug dealer. In the circumstances, if he thought it through, it was inappropriate given his position as Fianna Fáil’s justice spokesman.

In this instance the defence barrister drew the court’s attention to the constituent’s unfortunate circumstance: that the dealer was the sole carer of four children following the death by suicide of their mother earlier this year. The question is was it appropriate or necessary for the Fianna Fáil justice spokesman to do the same. The answer is no; and he apologised for it yesterday.

But there is something that is at least a little commendable in what was done. The man was not a constituent and there was no political gain for Collins in writing the letter. The four children also have rights under the Constitution and under law. Their mother died this year and the question of their their welfare and their care is not an irrelevant one. It would be impossible for anyone except the most bitter cynic not to believe Collins’s motivation was compassionate, driven by concern for the children. But like so many politicians before who have written such letters, and made representations, he had not fully thought through the consequences.

The man was convicted of being in possession for sale or supply of cannabis with a value of over €18,000. It’s not a minor offence, but it is certainly not egregious in nature. Unfortunately there are numerous examples of politicians who have made representations on behalf of convicted rapists, and have been pilloried for it when the knowledge became public.

FF justice spokesman Bobby Molloy was forced to resign after seeking temporary release for a rapist; Kathleen Lynch issued a

full apology after writing a letter supporting the family (and I have no doubt they were decent) of a rapist who was eventually sentenced to 14 years in prison. Collins’s difficulties were compounded by the fact he is his party’s justice spokesman. Tánaiste Eamon Gilmore overcriticised him, in my opinion, but was correct in saying that status added an extra dimension to it.

However, the clamour for Collins’s political head in the past two days has been typical of the recent tropes we have seen in the media, social media and in the world of politics. It has been distorted, disproportionate, Pavlovian – shooting from the hip and knee-jerk if both those things are simultaneously possible.

Among those whose responses were disproportionate was Taoiseach Enda Kenny. And irony of ironies, the politician who challenged his overstridency and populism was Fianna Fáil’s John McGuinness – no stranger to populism and hyberbole. Aithníonn ciaróg ciaróg eile.

The most over-the-top critique came from Sinn Féin councillor in Limerick Maurice Quinlivan, who is normally proportionate enough in his pronouncements. He said Collins should consider his position. And the tenor of his release was essentially condemnation of, and no mercy for, drug dealers.

I think that like Collins, politicians of every stripe should think through the consequences of their sentiments and pronouncements. Without sounding too fatuous about it, Quinlivan was not so quick to condemn the IRA gang who shot dead Garda Jerry McCabe in Adare in 1996. In 2007, 11 years afterwards, he was finding it difficult to use the word “condemn” about the action because he claimed it was not connected with Sinn Féin. The party has a legitimate right to speak out on justice matters, but its populism sometimes assumes a vacuum, that voids 30 years of awful transgressions.

Evidence as to the character or circumstances of a convicted person is required, and essential, during the sentencing hearing.

It is an integral part of the criminal justice process. The defence calls every imaginable person of standing in the community – employers, social workers, teachers, priests, doctors, youth leaders and sports officials – to give evidence of previous good character or particular circumstances.

This is to be expected and while it does not excuse the crime the judge gleans a more complete impression of previous character and of other extenuating circumstances. Indeed, these are factors that need to be considered when sentencing.

A suggestion made in some quarters was that Collins was furtively trying to exert influence on a judge. That was not the case. His letter was given to the man’s lawyers and presented to the judge in open court, much like any other written character testimony. But in all circumstances, his intervention was inappropriate. Should there be a hard and fast rule that politicians be excluded?

Prof Tom O’Malley of NUI Galway, an expert in sentencing, said in some cases, a politician (probably a councillor) might be in the best position to outline the circumstances.

Absolute prohibition Besides being legislators, they are also (and in Ireland particularly so) representatives of

community. But he said politicians should become involved only in exceptional circumstances, when no others would be in a position to give such evidence. An absolute prohibition is too broad.

The whips of all the parties attempted to come up with guidelines in 2008 after the Kathleen Lynch controversy but failed because it was too difficult to cover all eventualities.

Now Micheál Martin is suggesting the same. On the face of it, it’s a good idea. In realpolitik terms, though, the rule should be: don’t even think of intervening unless it is truly, truly, exceptional.