Case Law is the body of available writings explaining the verdicts in a case.
Case Law is most often created by judges in their rulings, when they write their decisions and give the reasoning behind them, as well as citing precedents in other cases and statutes that had a bearing on their decision. A single case may generate virtually no written interpretations or opinions, or, as is the case with many that come before the Supreme Court, it may generate a number of opinions as it works its way through various lower-circuit courts. These collected opinions can be referred to in the future by other judges when they make their rulings on similar cases, allowing the law to remain relatively consistent.