Trier of fact
A trier of fact (or finder of fact) is a person who determines facts in a legal proceeding. To determine a fact is to decide, from the evidence, whether something existed or some event occurred. In a jury trial, the jury is the trier of fact. The jury finds the facts and applies them to the law it is instructed by the judge to use in order to reach its verdict. Thus, in a jury trial, the findings of fact are made by the jury while the judge makes legal rulings as to what evidence will be heard by the jury and what law governs the case. The jury is supposed to strictly follow the law as given by the judge, but it does not always do so. In some cases this amounts to jury nullification, i.e. the jury effectively re-writing the law or blatantly ignoring it in a particular case.