If the case does go to court, the trial may have to take place on another planet.

Reuters

As millions of people rally online and thousands march in the streets demanding justice for Trayvon Martin, the state or federal prosecution of George Zimmerman seems increasingly likely. But ... as millions of people rally online and thousands march in the streets, Zimmerman's prospects for a fair trial seem increasingly unlikely.

I'm not questioning the outrage generated by Martin's killing and the cursory initial investigation of it. I'm not criticizing the campaign to re-open the case, the demand for federal intervention, or the skepticism about Zimmerman's story and his self-defense claim. I'm commenting on the dilemma posed by popular campaigns for criminal prosecutions: The effort to correct what appears to have been one grievous injustice risks creating another.

Public fury over high-profile murders naturally generates hunger for convictions, regardless of reasonable doubts.

If Zimmerman is indicted by state authorities for homicide, or for a federal hate crime, where in the world will the judiciary find an impartial jury? So many people have already convicted Zimmerman; so much prejudicial evidence and speculation have been so widely disseminated.

You can listen to the enhanced audio tape of Zimmerman's 911 call, including an arguably audible racial slur. You can read about Zimmerman's "long, lonely war against black people doing things." You can hear politicians and pundits ranging from Rick Santorum to Al Sharpton discrediting Zimmerman's "stand your ground" defense and demanding his arrest, and hear President Obama suggesting that Martin could have been his son. Or, you can join the nearly 2 million people who have signed a petition posted at change.org by Martin's parents calling for George Zimmerman's murder prosecution. Who doesn't harbor preconceptions about this case?

But if or when Zimmerman is indicted, assuming he isn't offered or doesn't take a plea, then somewhere, sometime a jury in his case will be empaneled. Imagine the pressure to convict and imagine the outrage if jurors acquit. Public fury over high-profile murders naturally generates public hunger for convictions, regardless of reasonable evidentiary doubts. In Boston last week, a courtroom erupted after a jury failed to convict two men in the "Mattapan massacre" -- the horrific, drug related executions of 4 people including one 2 year old child. The prosecution had a weak case, contingent on the testimony of an unsavory accomplice; the jury acquitted one defendant and was unable to reach a verdict on the other, (after voting 11 - 1 to convict).

Both defendants in the Mattapan case may be guilty, but given the evidence, the failure to convict can't simply be characterized as a failure of the jury system. The system will, however, be sorely tested by the re-trial of the accused shooter when, in the wake of widespread outrage over the first trial, the court seeks 12 jurors who don't believe that, this time around, it's their job to convict.  

In Boston, people demand justice for the victims of the Mattapan massacre; nationwide, they demand justice for Trayvon Martin. People always seek justice for murder victims, understandably, but trials are supposed to deliver justice to their alleged assailants. It's not easy finding jurors able to do so, according to the rules of evidence, in a highly publicized, emotionally resonant case. I doubt that I could sit fairly on George Zimmerman's jury and wonder who could. Where is there a venue not tainted by pre-trial publicity? They may have to try him on the moon.