So the jury plays no part at all in the legal system. It’s all based on the lawyers’ competence or in-. Juries are just as easily incompetent, but never as accountable. I’m sure Einstein would have had trouble teaching relativity to two-year olds or nonphysicists; but the fault wouldn’t be his competence.
Of course they do. However, in my thirty plus years of legal experience, I have never found a jury where all the jurors were dumb and stupid. It just is statistically highly unlikely.
Whenever, I lost a case I think I should have one, I never blamed the jury. Instead I went back to my office and tried to think the case through to determine why I failed to properly educate the jury. It's the only way you can improve your skills as a lawyer, and I would bet that is exactly what the prosecution is doing today.