In a modern democracy based on universal suffrage the political process is about working for the common good. Deciding what constitutes the common good involves a procedure based on convincing and persuading, not declaring and dictating. Society no longer consists of communities in which the laird, the dominie, the doctor and the priest or minister were the only educated people, expected to tell the rest of us what to think. As Scotland's most senior Roman Catholic, Cardinal Keith O'Brien is right to make known his opinions on various issues and offer his guidance to fellow Roman Catholics. The Herald does not hold to the view that the churches should stay out of politics. If anything, their voices should have been raised louder during the Holyrood election campaign. The Roman Catholic Church alone has more members than all of Scotland's political parties combined. It is entitled to articulate its stance on the key political concerns of the day.

In a modern democracy based on universal suffrage the political process is about working for the common good. Deciding what constitutes the common good involves a procedure based on convincing and persuading, not declaring and dictating. Society no longer consists of communities in which the laird, the dominie, the doctor and the priest or minister were the only educated people, expected to tell the rest of us what to think. As Scotland's most senior Roman Catholic, Cardinal Keith O'Brien is right to make known his opinions on various issues and offer his guidance to fellow Roman Catholics. The Herald does not hold to the view that the churches should stay out of politics. If anything, their voices should have been raised louder during the Holyrood election campaign. The Roman Catholic Church alone has more members than all of Scotland's political parties combined. It is entitled to articulate its stance on the key political concerns of the day.

However, Cardinal O'Brien's attack yesterday on pro-choice Catholic politicians was intemperate, inconsistent and ill-advised. He used a homily marking the 40th anniversary of the 1967 Abortion Act to urge parliamentarians to stop supporting what he called "an unspeakable crime" and warned them of "the barrier such co-operation erects to receiving Holy Communion". Though he later denied that he was saying such politicians should be excommunicated, his remarks were judgmental and threatening in tone. Though abortion is an issue reserved to Westminster, his remarks were clearly addressed also to members of the Scottish Parliament, which handles Scottish health policy.

Politicians are elected democratically to represent the views of constituents of all religious faiths and of none, whatever their own convictions. It is a fundamental tenet of a liberal democracy that they should not find themselves under threat as a result. The Abortion Act, for which MPs were allowed a free vote, reflected the broad public consensus of the time. Reducing the 28-week limit to 24 was in line with medical advances in the care of very premature babies rather than a reflection of a fundamental shift in public opinion, and similar considerations may prompt further reform in the near future. The contribution of churchmen, including Cardinal O'Brien, towards any such debate is welcome. However, he has only to survey those in the pews in front of him to see that many different views are represented in the modern Roman Catholic Church. Should couples who decide to limit their families by using modern contraception face the same censure he directs at pro-choice parliamentarians?

The Cardinal's remarks must be seen against the background of the Pope's recent visit to Brazil where he stirred up the row over abortion by suggesting that politicians who vote for abortion "exclude themselves from Communion". This is, in turn, a reprise of the tough line taken by the Vatican and American bishops against John Kerry during the 2004 presidential election. However, even within the Catholic Church there is disagreement about the provisions in canon law on this topic.

The Cardinal is right to be concerned about the rising number of abortions carried out in Scotland. But abortion is a complex issue in which the state cannot abdicate responsibility for public health. Generally speaking, women do not take such decisions without much soul-searching. Those who take this path need compassion, something the Roman Catholic Church excels at - witness the way the Pope was able to reach out to Kate and Gerry McCann in their time of need. The tone of Cardinal O'Brien's remarks, far from promoting sensible and intelligent dialogue on a difficult moral dilemma, merely polarises the debate.