In mid 2001, the CA heard "new" evidence of fraud, after it had sided with Greer. It then stopped the removal of the tubes telling the parents to show why Terri should be kept alive, again new evidence. Later in the year it directed Greer to hold another hearing to consider new technologies, again based on new evidence. Finally, it ordered the 5 doctor review which of course presented new evidence. So I would say they were quite active.
If one juror can convince the rest that there is a reasonable doubt as to the accused's guilt, the jury is supposed to acquit even if all the jurors are 90% certain the accused committed the crime. Whether or not you think that should be the case, that is clearly the design intention of the jury system and I see no reason to believe it did not work as intended in the cited cases.
When a jury can take about 1 hour to review a year's worth of evidence to find not guilty, justice has not been served. Jury nullification is an all to common practice. Why is that so sacrosanct? Frequently juries are in awe of celebrities such as Robert Blake and OJ, as well as their attorneys. At least with judges, celebrity attorneys don't trump lower paid prosecutors as they all too often do with juries. I have to accept it, but both cases show the weaknesses of juries.
But, in any case, if folks are upset with Greer, as I said before, impeach him or turn him out at election time.
Judge Ito should bear a significant portion of the blame for the Simpson trial result, since he allowed a ridiculous amount of showboating by defense counsel. The prosecuting attorney also made a number of mistakes. I don't see why a jury should be blamed for the fact that they were not given a good, solid, and unambiguous case to work with.
Basically, what jurors would have seen would be a bunch of investigators who could have acted to prevent evidence contamination but failed to do so. It may well be that investigators are often sloppy but defense counsel usually don't call them on it. Even if that's true, though, I would see no reason for jurors to excuse such sloppiness in evaluating the state's case.
My own personal belief about the O.J. case is that (1) Simpson most likely did kill the victims, but (2) there is a significant likelihood that some of the evidence may have been tainted, i.e. that the police framed a guilty man. To be sure, I haven't seen anything close to all the evidence the jury saw, but if I were on a jury and reached those conclusions, I would acquit.