Common Law is judge made law where courts create law where there is no present legal authority in the statutes or prior case law. Judges have the legal authority to create law by making precedent. Precedent is derived from common law and binds future decisions. When parties disagree on what the actual law is during a case, a common law court will look to past precedent of relevant court authority to rule on that issue. If a matter of dispute is unique from previous cases, it will be decided as a matter of first impression. Courts are very careful in crafting new laws and usually seek to avoid the issue if the materiality of the case does not hinge on the issue. This is common in Supreme Court cases where the justices will ignore an issue that is not necessary to decide the case.