In law, the standard of review is the amount of deference given by one court (or some other appellate tribunal) in reviewing a decision of a lower court or tribunal. A low standard of review means that the decision under review will be varied or overturned if the reviewing court considers there is any error at all in the lower court's decision. A high standard of review means that deference is accorded to the decision under review, so that it will not be disturbed just because the reviewing court might have decided the matter differently; it will be varied only if the higher court considers the decision to have obvious error. The standard of review may be set by statute or precedent (stare decisis). In the United States, "standard of review" also has a separate meaning concerning the level of deference the judiciary gives to Congress when ruling on the constitutionality of legislation.