THE PERPLEXING (and terrifying) thing about the history of Kevin Wiggins -- the Maryland death row inmate whose case will be heard by the U.S. Supreme Court -- is not how little evidence there is against him, not the fact that his IQ was 72 when he was 10 years old, not that his lawyers didn't fight for him at trial or that so many judges have expressed doubt about his guilt.

It's that all of those factors converge in one case -- and that despite them, this man's life still hangs in the balance.

Perhaps even scarier is the idea that the clouds of doubt that hang over Mr. Wiggins' case can also be seen lingering above other Maryland death row cases.

For the nation, the high court's decision in Mr. Wiggins' case could help clarify the difference between effective and deficient counsel in death penalty cases.

But for Maryland, the court's decision to hear the Wiggins case also adds to growing evidence that suggests this state must be more cautious with capital cases.

Already, Gov. Parris N. Glendening has refused to execute two prisoners because he doubted their guilt, and he has declared a moratorium on executions until a study concludes whether race taints the capital system. Before Mr. Glendening acted, several other death row inmates saw the cases against them crumble; Maryland's death row has shrunk by almost half since 1999, without any executions.

And though Mr. Wiggins' case is not yet on the scrap heap, its problems are classic.

Prosecutors never really proved he murdered 77-year-old Florence Lacs in 1988. The closest they came was showing that he was in possession of her car and credit cards after she was killed. His fingerprints weren't found in Ms. Lacs' house, but five other unidentified prints were.

His attorneys didn't introduce evidence at sentencing about the horrible physical abuse Mr. Wiggins suffered as a child or his limited mental capabilities.

And in subsequent appeals, several judges have questioned both the sufficiency of the evidence against Mr. Wiggins and, more prominently, the effectiveness of his defense attorneys. But Maryland's highest court twice upheld his conviction, and the 4th U.S. Circuit Court of Appeals reversed a lower federal court's overturning of the death sentence -- even though the 4th Circuit's chief judge implored the governor to consider granting clemency.

Mr. Wiggins' case shows how difficult it is to reverse a death sentence, no matter how compelling the arguments against it. And his difficulties are not isolated. Anthony Grandison, a mentally limited death row prisoner who was allowed to defend himself at trial, has faced similar hurdles. The evidence against Wesley Baker was also questioned by an appeals court judge, but he faced imminent execution before the governor declared a moratorium.

In a sense, the system has a chance to get things right up until the day a prisoner is strapped to a gurney and a lethal injection is pumped into his veins. But shouldn't it be better at administering justice before the last minute? Shouldn't the system have more safeguards to prevent undeserved death sentences in the first place?

Mr. Wiggins' case suggests it should. And no matter what the Supreme Court decides, it's clear that Maryland has a lot of work to do to make the capital system fairer.