If a US Attorney were to charge Sheridan Peterson with the skyjack, I predict he would walk away a free man. The standard for conviction is and will always be PROOF BEYOND A REASONABLE DOUBT. None of the circumstantial evidence against him, even taken cumulatively, reaches that standard. Not even close. The FBI undoubtedly knows this. Remember, their role is not to "solve" the case but rather to present a prosecutable and winnable case. "Knowing" who Cooper is and being able to successfully prosecute Cooper are two very different things.
I had a client (now deceased) who the FBI "KNEW" had committed a serious crime but they didn't have enough evidence to prosecute. The US Attorney's Office instead went after him for federal loan fraud and won. The sentence was heavy because the judge probably shared the FBI's opinion that he had done much more. Although he was never late on a single mortgage payment, he had lied about sources of income on the loan application. It was like going after Al Capone for tax fraud when they couldn't prove anything else.
If Sheridan were charged, I'd volunteer to represent him pro bono. I am retiring soon and it would be a great retirement project. I believe I could get the case dismissed prior to trial based on the FBI's loss of the cigarette butts. The butts, if they had a good DNA sample, could convict someone, but they could also exonerate someone who was a possible match to the partial DNA found on the tie. Their loss is a loss of possibly exculpatory physical evidence, which is usually fatal to a criminal prosecution. That loss of potentially exculpatory physical evidence could be rendered harmless, however, by a credible and legally admissible confession or by the discovery of other unequivocally incriminating physical evidence.
And by the way, when you lose critical evidence, all the presumptions are construed against the party who lost it. Protests that the butts would not have had good DNA and therefore their loss should not result in a dismissal will very likely fall on deaf judicial ears.
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