What is the test for determining the sufficiency of evidence in a civil case?

Both parties rely on the doctrine of law of the case, which applies to both civil and criminal cases. (People v. Shuey (1975) 13 Cal.3d 835, 841-842.) The doctrine, "as the name implies, is exclusively concerned with issues of law and not fact. [Citations.] Examples abound, and include the legal sufficiency of evidence [citations], the sufficiency of pleadings [citations], the nature and effect of a document [citation], and appellate jurisdiction itself [citations]." (Id. at p. 842.)