One of the common cases made against capital punishment is that it is too-often enforced unequally along racial and socio-economic lines. In response to this, Ernest van den Haag (”In Defense of the Death Penalty”) offers an argument that I think has implications for a more general issue in philosophy of law, namely the problem of selective prosecution.

If the death penalty is morally just, however discriminatorily applied to only some of the guilty, it remains just in each case in which it is applied.

…[U]nequal justice is still justice. The guilty do not become innocent or less deserving of punishment because others escaped it. Nor does any innocent deserve punishment because others suffer it. Justice remains just, however unequal. While both are desired, justice and equality are not identical. Equality before the law should be extended and enforced - but not at the expense of justice.

There are obviously other arguments for and against the death penalty but, for the purposes of this post, I wish to focus on Van den Haag’s assumption that “unequal justice is still justice”. There’s one sense in which it’s clearly true. If Smith is convicted of murder and if the death penalty is justified for all murderers, then it follows that Smith deserves death regardless of how many murderers are acquitted. In fact, without this assumption, most of our penal system would be unjustified. The guilty are often acquitted and those convicted often receive lighter sentences for a variety of reasons.

It’s true, as Van den Haag claims, that “justice and equality are not identical”. Perhaps, though, justice and equality are related in a different way. Justice may require equality, or at least prohibit systematic inequality. Imagine a state that, in an effort to compromise between death-penalty supporters and opponents, passes legislation that all and only convicted murderers born in months with 30 days shall be put to death. Would we say in this case that “unequal justice is still justice”? And if not, how does it differ from the kind of cases Van den Haag has in mind? (Ronald Dworkin makes a similar argument for integrity as an independent legal and political virtue. I posted about it here.)

In the case of a person put to death under the law that specifies that only those born in months with 30 days are candidates for capital punishment, justice is only partially served. Yes, a convicted murderer received the punishment for murder but the state has acted in a way that undetermines its ability to mete out justice. Systematic inequality is, in and of itself, unjust and thus, the very existence and application of such a law is a crime against justice.

The death penalty, more than typical jail sentences, is prone to unfair racial discrimination and capriciousness regarding what kinds of murder warrant death. What’s worse, the nature of the penalty makes reversing it impossible. And while individuals receiving a punishment they deserve is justified, the state, in enforcing such a punishment, may not be.