The case for
Those who defend the jury's power to acquit against the evidence make an argument about where the last word should sit. A law is written by a legislature and applied by a judge, but it is enforced against one person, in one room, by twelve others from the community. If those twelve will not convict, the argument runs, that is the community's judgment on the law as applied to that case, and the system was built to allow it. The power is old, it is part of why the jury exists, and it cannot be taken away without taking away the general verdict itself.
The case against
Those who argue the other way make an argument about equality before the law. A law that one jury enforces and another refuses to enforce is not the same law for everyone. A jury that decides on something other than the evidence can act on sympathy, but it can also act on prejudice, and history holds examples of both. The instruction to follow the law as the judge gives it exists, on this view, so that the outcome of a trial depends on what was proved and not on who happened to be in the jury box.
Who makes each case
Both arguments are made by courts, by lawyers, by scholars and by advocacy groups, and both have been made for a very long time. Courts have mostly settled on the instruction: tell jurors to follow the law, and do not tell them about the power. Legislatures have, in a few places, written something about the jury's role into a statute or a constitution. Advocacy on both sides continues outside the courtroom. This guide does not rank those voices or pick among them.
Where this guide stands
JuryNull takes no side in the debate. It is a reference, and its job is to report what the law of each jurisdiction says about the jury's power, the instruction, selection, the verdict and the juror, in that jurisdiction's own words and with the source for each. Readers who want to weigh the arguments can do so against the law as it actually stands where they live, which is what the chapters are for.