Jonathan Romain discusses the circumstances in which one should forgive. Though some people, he says, are 'prepared to forgive a wrongdoer whether or not he/she shows any contrition', he for his part is not; he thinks that 'a key condition is that the person who perpetrated the hurt shows remorse'. This is the view I would also take, at least where we're thinking about wrongs of a very grave sort. I may at some point write about this question in a more general way, but for the time being I want to concentrate on just one aspect of it that Romain himself says nothing about.
For present purposes I will simply take the Wikipedia formula - it overlaps with the definition given by the New Shorter Oxford - that forgiveness involves abandoning any 'resentment, indignation or anger' over some offence. Now, let us assume we are faced with someone guilty of mass murder but who is completely unrepentant about it. They reaffirm that they are at ease about what they have done, even that they would do the same thing again. Can it be right to forgive such a person?
The aspect of the question that interests me is this one: since this person reaffirms the attitude of mind with which they committed their horrible crime, to feel no anger or indignation or resentment - to be either benevolently or neutrally disposed - towards them is tantamount to feeling the same way even while they are committing the crime (or towards someone else who is doing likewise). You might as well forgive them at the time of the crime - or indeed, should you somehow come to have foreknowledge, in advance of it - since nothing in their moral character or disposition or outlook has changed between the earlier and later periods. This is a step too far towards tolerant understanding and indulgence. It is, in effect, a willingness to forgive everything in advance; which seems to me a bit like condoning it.
That, at any rate, is the hypothesis I propose unless and until somebody should talk me out of it.