October was a notable month: For the first time in three years, America went without an execution. For those opposed to the death penalty, this would seem to be good news. Sadly, it is not.

The Supreme Court granted three stays of execution in October in anticipation of Baze v. Rees, a case it will hear in January. Baze will likely determine the constitutionality of lethal injection (the mode of execution used by all but one of the 38 states that sanction the death penalty), so it’s possible there will be no executions for the rest of this year.

If so, 2007 will have seen only 42 inmates executed, the lowest total since 1994 and a number that has trended down since a high of 98 in 1999. If the number is to shrink further, however, an intellectual framework of opposition to the death penalty must be erected.

And there is one, one a conservative can make, with not only a clear conscience but also a motivated one. It’s an argument conservatives should begin to make in larger and larger numbers, on behalf of us all.

There are three possible paths for opposition to capital punishment, two of which lead only to wilderness.

The first is the appeal to legalism. Baze, for instance, attempts to skirt the law by challenging the legality not of the death penalty itself but of its prevailing instrument. However well-intentioned this type of challenge may be (and contra the Supreme Court’s 1972 Furman v. Georgia decision), there is no convincing legal argument against capital punishment per se. The Fourteenth Amendment allows that no state shall “deprive any person of life, liberty, or property, without due process of law.” The clear implication is that as long as due process is followed, a state may indeed deprive someone of his life. Attempts at legally maneuvering around the death penalty are ultimately useless. Or worse.

The second pathway is by “prudential” argument – arguing, in effect, that capital punishment simply can’t be made to work well. Some contend, for example, that capital punishment is simply too logistically flawed to maintain. That’s what George Ryan, then the governor of Illinois, decided when he put a moratorium on his state’s executions and commuted the sentences of all 167 of its death-row inmates because he believed the process was broken. Twelve Illinois men had been executed since 1977, while 13 convicted and sentenced to die had been eventually exonerated and set free.

There are legitimate concerns about the ability to conduct fair trials, the lack of competent representation, the fallibility of law-enforcement officers, and the impact of race in many death-penalty cases.

The problem with prudential arguments is that they can be employed just as easily on behalf of capital punishment. Proponents argue that the death penalty acts as a deterrent to would-be criminals. There is no way to find hard numbers to back this claim, but it may be true. Between 1930 and 1940, a much safer time in a much smaller America, anywhere from 140 to 199 people were executed every year. It’s plausible that the broader application of the death sentence in those days may have helped keep crime in check.

But the only grounds on which an enduring argument can be made against capital punishment are moral grounds. The moral argument goes something like this:

As Joseph Bottum once noted, in the course of earthly governance, “justice and mercy are necessarily ‘in conflict.’ ” Society’s ability to provide the former is limited; the ability to show the latter is not.

The “culture of life” – which protects the most vulnerable among us, from the unborn to the severely disabled and elderly – is strengthened when our society chooses mercy over justice. This choice strengthens us, just as surely as the choice of death hardens us.

Finally, by attempting to provide cosmic justice for the disordered act of murder, the state arrogates divine authority unto itself. This is the very authority Western nations rejected when they turned from monarchy, the very kind that falls into conflict with the idea of the secular state. The enactment of capital punishment is something like the establishment of a state religion.

All of which adds up to the notion that government should not be in the business of killing unless it absolutely must in order to protect the innocent.

And here is the one case where the prudential unhappily intrudes on the moral: If the existence of a criminal poses an ongoing threat, then the death penalty can be a necessary evil. Such cases are incredibly rare, limited mostly to heads of criminal states or organizations. For instance, an imprisoned Osama bin Laden would pose a continuing threat to the citizenry by inspiring violence in ways a mere murderer, or even a serial killer, would not.

Yet the list of such hypotheticals can be counted on one hand. The overarching case is there to be made that the death penalty should be put aside in America – not because it’s unconstitutional, or because it doesn’t work well, but because it’s wrong. And this should be accomplished not by courts torturing the law, but by citizens and legislators changing the laws.

It is a difficult and complicated task – not least because the task includes changing the minds of the vast majority of Americans who approve of capital punishment. But it is one worth undertaking nonetheless.