In In re Estate of Montemayor, a buyer sued a seller regarding five real estate contracts. No. 09-21-00054-CV, 2023 Tex. App. LEXIS 1174 (Tex. App.—Beaumont May 13, 2022, no pet. history). The seller’s executor alleged that the contracts were not enforceable because the seller did not have mental capacity to execute them. The jury found for the buyer, and the seller appealed.

The court of appeals first addressed the standards for mental competence to contract:

Mental incapacity is a common law defense to the formation of a contract. Texas law presumes that a person executing a contract or instrument had sufficient mental capacity at the time of its execution to understand his legal rights. Accordingly, the burden rests on the person seeking to set aside a contract or instrument to show the lack of mental capacity of the contracting party at the time the contract or instrument was made. To establish lack of mental capacity to contract in Texas, the evidence must show that, at the time of contracting, the person could not have “‘appreciated the effect of what [he] was doing and understood the nature and consequences of [his] acts and the business [he] was transacting.'” The proper inquiry is whether the person had capacity on the days he executed the documents at issue. Generally, the question of whether a person, at the time of contracting, knows or understands the nature and consequences of his actions is a question of fact.

Id. The court then reviewed evidence from the buyer that the seller knew what he was doing and acted normally in conversations, evidence from a long-time friend that the seller had complained about the taxes associated with the property and felt the seller was lucid, and evidence that medical records showed that the seller was oriented and had normal cognition during the relevant time period. The court affirmed the jury’s verdict for the buyer.