The recent suggestion by veteran anti-apartheid journalist Max du Preez that the possibility of offering Jacob Zuma a plea bargain should be seriously considered is only the latest in a series of suggestions by seasoned commentators for a way out of what may well be South Africa's most serious political crisis since 1994.

This crisis is one that some acolytes of Zuma have created through their threats to wreak havoc if he is convicted and barred from the country's presidency.

Plea bargains are morally problematic at the best of times. Under such bargains, prosecutors concede to punishments that are less severe than justice would require.

Such departures from justice require justification. Sometimes they are defended on probabilistic grounds.

That is to say, attaining a certain guilty plea is considered preferable to gambling all on the less sure prospect of a conviction: a guilty plea in the hand is worth two convictions in the bush.

Du Preez is not invoking this justification. His fear is not that Zuma will be unjustly acquitted, but rather that he will be convicted.

A second way in which plea bargains are defended is with reference to limited judicial resources. Justice comes at a financial price because trials are costly.

Sometimes, it is thought, compromising justice via a plea bargain can be compensated by the pursuit of justice in other cases with the resources the plea bargain makes available. This justification cannot be employed in the case of Zuma.

Holding high public officials to account is a top priority not only because they have the most power to avoid such accountability, but also because the wellbeing of the entire society depends on checking the power of the most powerful. One offers plea bargains to small fish in order to convict big fish - not the other way around.

A deal for Zuma would be more problematic than ordinary plea bargains in a further way. If it were to attain its stated goal - avoiding national instability - its terms could not preclude Zuma from becoming president.

As such it would be a capitulation to a threat rather than a genuine compromise of competing claims of justice.

Du Preez notes that there is ample precedent for such a deal. Here he points, for instance, to a deal for Winnie Madikizela-Mandela and amnesty for many apartheid-era perpetrators.

These deals, of course, are deeply problematic themselves. The Truth and Reconciliation Commission, for example, denied justice to thousands of victims, offering them instead snippets of truth, requests for reconciliation and minimal compensation.

Since many wrongs do not make a right, appealing to South Africa's history of impunity is not sufficient to justify yet another case.

The reasoning underpinning Du Preez's suggestion, as well as its precedents, is a seductive utilitarianism, according to which we ought to do whatever produces the most good - or the least bad. This sort of reasoning has considerable popular appeal, particularly in political contexts. However, it is deeply flawed.

In its crudest forms, it sacrifices considerations of justice on the altar of the common good. That end justifies any means necessary to attain it.

A more nuanced utilitarianism recognises that such sacrifices, although they may produce better consequences in the short term, are counterproductive in the longer term.

The more one capitulates to threats, the more one encourages people to make such threats. Averting one crisis by compromise only encourages future crises, which in turn can only be averted by further compromises. The outcome is the very antithesis of the common good.

Thus, the Kenyan deal in the wake of that country's recent post-election violence encourages future losers in elections to foment violence rather than to concede defeat.

Similarly, any accommodation made with Robert Mugabe in order to rescue Zimbabwe from his clutch will, as Allister Sparks put it ("Negotiating with hostage-taker Mugabe sends a terrible message to tyrants", Cape Times, August 20), encourage other tyrants.

Although not of the same order, cutting a deal for Zuma would be nationally damaging. It would exacerbate an already widespread disrespect for the law, reinforce a culture of impunity and consolidate an absence of accountability.

It would make a mockery of our Rechtsstaat, a society underpinned by the rule of law, a central pillar of our much-vaunted democracy.

What is the purpose of a carefully crafted legal system if it can become the plaything of politicians, subject to cynical backroom deals when the going gets tough?

Even if there were a case to be made for drawing a line behind human rights violations perpetrated in the apartheid era as a means of transitioning to a democratic South Africa, such rationales cannot be employed within a democracy.

In other words, while some might argue that the earlier deal was essential to the establishment of liberal democracy, the proposed Zuma deal is clearly a threat to South Africa's future as a society governed by the rule of law.

*David Benatar is Professor of Philosophy at the University of Cape Town. Milton Shain is a Professor in the Department of Historical Studies. This article first appeared in the Cape Times September 1 2008

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