Summary of Williams v. Glash
S. Ct Tx 789 S W 2d 261 
Avoidance of the K: Mutual Mistake
Relevant Facts: Pls, Williams were involved in a car accident w/ no immediate injuries. The Df Ins co estimated the repair costs and provided a check in that amt. Pl completed claim form which asked if an injury existed, she put NO. There was no negot or bargaining for release, but the reverse of the check contained language purporting to release P I claims which was never explained or discussed. On its face was a property damage code “200-1″ not a P I code. Pl was later diagnosed w/ and injury attributed to the accident.
Legal Issue(s): Whether execution of the RELEASE for P Injuries bars a subsequent suit for an injury unknown at the time of signing?
Court’s Holding: Release may be set aside under mutual mistake doctrine.
Procedure: Tr Ct Summary for Dfs; Ct of App Affirmed (both tr and app cts found suit was barred by execution of release); S. Ct Tx Reverse and remand.
Law or Rule(s): A release is a K, and subject to avoidance on grounds such as fraud, mistake. When the parties have Ked under a misconception or ignorance of a material fact, the agreement will be avoided. PER does not bar extrinsic proof of mutual mistake, and mutual mistake does not preclude a person from intentionally assuming the risk of unknown injuries in a valid release.
Court Rationale: If the parties intent to cover an unknown injury from the language of the release can’t be determined, then consider their conduct and the information available at the time of signing. Once a release has been plead and proven, the B o’ P is on the party seeking to avoid to establish mutual mistake. Mutual mistake is determined by circumstances surrounding execution of the release, such as knowledge of the parties, amt of consideration paid, extent of negotiations/discussion as to P I; haste or lack in obtaining release.
We do not release an injured tort victim from an unfair bargain, but the law of mutual mistake applies to P I releases the same as other Ks. If it can be established that release sets out a bargain that was never made, it will be invalidated.
Plaintiff’s Argument: The Dfs and Pl never entered into an agreement to settle or release Dfs from liability related to an injury b/c the injury was unknown at the time they signed the release.
Defendant’s Argument: Texas law mandates that the parties intent may be looked at for the purpose of interpreting and applying the release, but not to alter the unambiguous language of the K.
DISSENT: The law favor peaceful settlement and orderly resolution of claims and also favors just compensation of accident victims. Cts cannot legitimately cast themselves in the role of saving people from bad bargains. Any mistake as to the nature of injuries at the time of settlement is strictly a unilateral one, not mutual. If the ins co refuses to settle they are subject to bad faith claims, if they settle promptly they are not protected from later assertions of unknown injuries.