I envy the legal systems of states utilizing bench trials. The defendants who got to have a judge decide the case don't have to worry about racial bias in the selection of jurors, nor will there be any concern the trier of facts is ignorant of the law, unfamiliar with crime scene contamination, falsified confessions, statistics, serology, DNA and ballistics reports, psychiatric diagnoses, the fallibility of witnesses, and other expert testimony. That's because the judge is an expert in the practice and knowledge of the law, and he or she is well qualified to deal with anything an attorney brings up.
Juries, by contrast, are generally ignorant of the law even when given uncomplicated instructions about a very small part of it. Jurors are typically the last people to know anything about a case, unless they've researched it online or otherwise heard about it prior to selection. As a collection of "peers" it can only be said they are human beings who are susceptible to suggestion, lies, personal bias, and the misfortune of being forced to do their civic duty. The very last thing an ordinary member of the community should be is a trier of facts in a court room, but this is the legal system we have in America.
It's a shame, really, that attorneys must rely on this group of lay people to comprehend their arguments. Some jurors try real hard to pay attention to the facts, but a savvy prosecutor can manipulate emotions and command the jury's allegiance without ever referencing the truth. No matter how twisted the logic or histrionic their actions, emotional appeals to the unwary work under most circumstances. Take, for example, DNA evidence. It requires expert testimony to interpret laboratory results but a jury will only hear what a prosecutor screams or objects to. The DNA expert is subject to be ignored in the wake of a fiery "I OBJECT!" A judge might better understand the nuances of a particular science, but the jury? Forget it.
If a judge were asked to consider a death sentence as a possible punishment, but first they must determine guilt or innocence, I believe he or she could compartmentalize each phase of the trial and remain impartial. Ordinary citizens (let's stop calling them peers) who think about bills, lost wages, childcare, and a thousand other things besides the facts in a case, are unlikely to pay attention let alone remain impartial. They are not trained jurists, merely victims of a bureaucratic lottery that provides the illusion of fairness on imbalanced scales of justice.
Juries area critical problem plaguing the criminal justice system, a fatal flaw upon which is heaped the most responsibility in the courtroom. Even a barely competent defendant has a better chance of understanding the process simply because he or she has a vested interest. The bailiff, who is little more than basic security, likely knows more about trying facts than any citizen juror unless they've had prior experience. If such were discovered during voir dire the potential juror would be dismissed. Well meaning jurors are supposed to be ignorant, but intuitive enough to listen and be critical of both sides while carefully weighing the facts as they apply to the law. I would rather take my chances playing Russian roulette with five bullets and one empty chamber.
Fortunately, jury trials are not that common. About 90% of criminal cases never go to trial, instead plea bargains are struck to save time and money while keeping the bowels of the system loose. For the unfortunate percentage forced into jury trials they must undergo the farce that is an understanding and impartial jury. It doesn't have to be this way.
The best solution is to eliminate forced jury trials and grant the option of a bench trial in every criminal case -- especially those involving capital murder.
If I am to be compelled into a situation where my life and liberty depend on who is paying attention to the arguments in a case, then I want an expert to decide my fate, not a group of strangers who may not mean well and will probably think of everything but the facts. If whether or not I spend the rest of my life in a prison cell or die by lethal injection depends on what kind of person my trier of facts is than, please God, give me a bench trial every time. At least this way, with one qualified judge, I stand a better chance of receiving justice rather than the mythical version that is the jury trial.