SOUTH CAROLINA IS one step away from becoming apparently the first state to thumb its nose at medical ethics, social mores and federal law and start paying people to sell Granny’s liver.

A bill passed in the hectic final days of the legislative session offers a $1,000 tax credit for the estate of any S.C. resident whose tissues or organs are donated.

The legislation is a well-intended attempt to serve a very real societal need for more donated organs to keep pace with the growing number of people whose lives could be saved with a transplant. More than 85,000 Americans (704 of them South Carolinians) need transplants, but last year only 6,500 were performed. So 6,103 people died waiting. Fewer than a third of the people whose organs could be donated actually become donors, largely because even when people register as organ donors, their families either don’t know about it or else overrule their decisions when called upon to make the crucial, life-or-death call.

Well-intended as the financial incentive is, though, it is a horrible idea — one Gov. Mark Sanford needs to make sure does not become state law.

The reason for the ethical denunciation, and the federal ban, of paying for organs is simple: If a financial incentive is offered for organ donations, someone must determine what the financial incentive will be. Whether intended that way or not, the mere act of deciding that number has the effect of putting a price tag on the value of the organ — and of the human life it may save.

As if that idea isn’t repulsive enough on its face, consider that the only way you could offer an incentive without creating price wars in which the highest bidder gets to literally buy a life-saving organ from another human being is for the incentive-giving to be limited to government. That means the very act of setting a price on human life would become part of an annual budget-writing process, with all the compromises that are a necessary part of that process. The economy’s slow? Well, we’ll just cut the value of a human life by half, so we can still afford programs with a larger constituency.

Many medical professionals, faced with disappointing results from public awareness campaigns aimed at promoting organ donation, are starting to dip their toes into a debate over whether the taboo — and the federal law — against paying people for organs should be relaxed. The Congress and a handful of states have taken a tiny step toward financial incentives, with laws to use tax credits to reimburse living donors for any expenses not covered by insurance — typically travel to and from a transplant center and pay for time off from work. And in fact, that’s what the bill that passed the S.C. House and came before the state Senate last month was intended to do.

Unfortunately, what happened far too often in South Carolina happened next: During the lightning-fast consideration that is given to bills with no opposition, an amendment was proposed. That amendment, couched in terms of encouraging people to donate urgently needed organs, sounded good if you didn’t think about it too long. And so without the careful ethical debate that is occurring nationally, without that thinking-about-it-very-long process having occurred, the Senate voted unanimously to pay people to donate their dead relatives’ organs. The next week, the House, just as quickly, agreed to the addition. And now it’s up to Mr. Sanford to veto a well-intended but unethical, socially questionable, illegal bill. He should do so soon.