Blue Cross Health Services, Inc. v. Sauer
Missouri Court of Appeals
800 S.W.2d 72 (1990)
A hospital mistakenly linked patient William R. Sauer to an insured namesake, William J. Sauer, causing Blue Cross (plaintiff) to mail over $22,000 in checks intended for William J. to William R.'s address, where William R., his father, and his father's business (defendants) cashed or deposited them. After discovering the mix-up, Blue Cross sued in equity for a constructive trust based on unjust enrichment; the trial court initially entered judgment for Blue Cross but then granted a new trial after ruling the defendants had been wrongly denied a jury trial, and Blue Cross appealed.
Whether a person who pays money to another by mistake is entitled to restitution from the payee even though the mistake was due solely to the payor's own lack of care.