(CBS) Attorney Andrew Cohen analyzes legal issues for CBSNews.com.

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The next time you have an urge to declare someone guilty before trial, someone like, say, Scott Peterson or Martha Stewart, think of Lizzie White. The next time you hear a post-arrest press conference where prosecutors and the police declare their case a slam dunk, think of Joe Moore. The next time you think that monstrous injustice is a thing of the past in our legal system, think of the Tulia Twelve.

The West Texas defendants -- White and Moore among them -- who were falsely accused and then improperly convicted for drug trafficking represent the flip side of the legal lollapalooza we’ve seen lately in the Peterson and Stewart cases. No slick lawyer came on television after these men and women were arrested back in 1999 to spin their cases for the primetime talk shows. No one covered the hearings or trials live on cable news or produced one-hour specials full of slow-motion action shots. No witness hired her own attorney to handle media requests and potential book deals.

Instead, as the Washington Post reported, “in eight lightning-quick trials, juries with virtually no black members handed down blisteringly tough sentences -- even though the sweeps turned up no drugs, weapons, paraphernalia or other signs of drug dealing.” When the rest of the defendants saw that -- Jim Crow justice 50 years after it was supposed to have been outlawed -- they quickly pleaded guilty themselves in order to give themselves at least a shot at a lighter sentence. And then they languished in jail, knowing they were innocent of those charges, until sufficient legal momentum and good old-fashioned outrage did something about it.

These convictions and guilty pleas occurred before anyone suspected that the lone detective who carried out the undercover investigation was himself a bit of a fraud. Tom Coleman, now under indictment himself, “did not record his purchases, and he worked alone. His notes sometimes consisted of his jotting down broad information about sales on his leg,” the New York Times reported. There is nothing inherently illegal or improper about that. But defense attorneys, prosecutors and the judge now agree that Coleman engaged in “blatant perjury” while on the witness stand in the cases and was “the most devious” witness the judge had witnessed in his “25 years on the bench in Texas.”

Jayson Blair meets C.S.I. Miami, you might say. Yet Coleman’s testimony, alone, was enough to put people in jail, some under sentences as long as 90 years. That tells you all you need to know about easy and simple it is to twist all the preconceived notions and assumptions we have about fair and equal justice in America. And in this Age of Laci and Larry King, when people are so quick to make such important judgments about people they’ve never met based upon evidence they’ve never seen, it’s hard to imagine a better time in the history of the law for a story that reminds people that things are rarely what they seem.

I can just see the angry phone calls and e-mails coming to my poor editors so, please, let’s get it straight. I’m not guaranteeing that the Tulia defendants all were or are angels. And I’m not saying that the police have lied in the Peterson case or that federal law enforcement officials have made out of origami their case against Stewart. I hope that they haven’t -- and that would be the way to bet, too -- but the fact of the matter is that you just never know about a case, a defendant, a prosecutor, a cop, a witness, a judge, a lawyer, the evidence, whatever, until it all comes out in the open. And even then, as we’ve seen with these poor folks from Tulia, there are no guarantees. I wish they would talk about that sometime when they gather the talking heads together for their ritualistic speculation frenzy each night.

The story of the Tulia two-step is neither prevalent nor unheard of. It happens from time to time in our all-too-human justice system. And the truly awful thing about it is that you never really know it’s happening until long after it’s happened. If you don’t believe me, ask the Illinois death-row inmates who were wrongly convicted how it feels to be truly worthy of primetime attention -- only to find that the spotlight and its glare are elsewhere.