The telltale strand of the victim's hair wasn't. It wasn't the victim's.

The hair was the only significant physical evidence in the case that sent Michael Rivera to Death Row 16 years ago. The jurors who convicted Rivera were led to believe that blond hair found in a van borrowed by Rivera had come from a strangled little girl.

So many years later, DNA testing proved otherwise.

Once again, doubts, like a pack of feral dogs, stalk the Broward County criminal justice system.

Not that Michael Rivera makes an appealing model for the wrongly convicted. He was, back in 1986, an appalling pervert, writhing with repulsive sexual fantasies, with a conviction for attacking another child. Nobody would have cared much if cops had jimmied the evidence to send him to prison for the rest of his life. It's just that we pretend to have higher standards before we kill our convicts.

Of course, other men wrongly convicted of murder in the 1980s by the Broward Sheriff's Office's runaway homicide squad were also unsavory characters. A bum rap fit both Frank Lee Smith and Jerry Frank Townsend so nicely that judges and prosecutors, who should have known better, ignored the emptiness of the evidence.

Meanwhile, the actual killer, a psychopath named Eddie Lee Mosley, continued his serial murder spree.

Remember, somebody monstrous murdered 11-year-old Staci Jazvac in 1986. The state intends to execute Rivera for the crime. But wouldn't it have been nice if the DNA had matched the prosecution theory? Wouldn't it be nice if we were confident that the guy on Death Row was Staci's actual killer?

Those blond hairs had buttressed the prosecution's contention that Rivera had snatched Staci off the streets of Lauderdale Lakes, forced her into a borrowed van, strangled her and dumped the body in a field in Coral Springs.

DNA undid that premise. Of course the prosecution still has the testimony of Frank Zuccarello, South Florida's most notorious jailhouse snitch.

Zuccarello bartered 23 felony charges down to less than three years in prison by providing key testimony in homicide cases, though a BSO investigator in another case characterized him as ``an untrustworthy witness who should not be believed under oath or otherwise.''

Yet it was Zuccarello who delivered such dramatic testimony in the 1987 trial, describing how Rivera, his cellmate in jail, had admitted killing Staci. Wouldn't it be nice if the star witness in a death penalty case possessed just a hair of credibility?

Rivera might have been convicted -- without the hair strands, without Zuccarello and two other dubious jailhouse snitches -- just on the murderous fantasies he had concocted and described to others about Staci after the murder. Or by the incriminating statements extracted from him during his interrogation by the BSO.

Except, in retrospect, the admissions seem too reminiscent of the false confessions the BSO elicited in other, now discredited homicide cases.

The flaws in the Rivera case are just too familiar. We'd like to kill our Death Row convicts, even the most perverted, sure that they're actual murderers.

But so many doubts stalk the conscience.