How might the jury in deliberation have decided which side came to the correct results?

Expert witnesses testify at many criminal trials for both the prosecution and defense. The variety of possible expert witnesses is virtually limitless. Although experts must be determined qualified by the trial judge in order to be permitted to state an opinion, some expert testimony is really based on “junk science.”

How might the jury in deliberation have decided which side came to the correct results? This is a key issue. If the cause of death was heart failure brought on by exertion–the police contact–then intent to kill may be questionable. Remember to evaluate the expert witnesses. This is not meant to be a discussion of the case or of its result. Do you believe expert witnesses assist the jury in understanding and evaluating complex concepts or just spin the facts to support the position of the side that hired them?
Do you think juries place too much emphasis on their opinions, or can average jurors effectively assess their credibility and weigh their testimony for what it’s worth?
Do you think enough is being done to keep “junk science” out of criminal trials?