Can a presumed father rescind a voluntary denial of paternity based on mistake of fact? Mackley v. Openshaw Explained

In Mackley v. Openshaw, the Utah Supreme Court addressed when a presumed father can rescind a voluntary denial of paternity under the Utah Uniform Parentage Act (UUPA). The court’s holding clarifies the crucial distinction between mistakes of fact and mistakes of law in paternity proceedings.

Background and Facts

Adam Mackley conceived a child with Adrienne Openshaw while she was married to Colton Barney. After genetic testing established Mackley’s biological paternity with 99.99 percent probability, the parties signed a voluntary declaration of paternity and denial of paternity at the Utah County Health Department. Barney, as the presumed father, signed the denial affirming under penalty of perjury that he was “NOT THE BIOLOGICAL FATHER OF THE CHILD.” However, none of the parties fully understood that this would legally terminate Barney’s parental rights as the presumed father.

Key Legal Issues

The central issue was whether Barney could rescind his voluntary denial of paternity based on mutual and unilateral mistake of fact. Under Utah Code § 78B-15-307(1), after the statutory rescission period expires, a signatory may challenge a denial “only on the basis of fraud, duress, or material mistake of fact.” The district court found that all parties were mistaken about the legal consequences of signing the form and allowed rescission.

Court’s Analysis and Holding

The Utah Supreme Court reversed, holding that the district court erred in allowing rescission. The court emphasized that equitable rescission doctrines relate to mistakes of fact, not law. Here, any mistake concerned the legal consequences of signing the denial rather than underlying facts. The court noted that “each party has the burden to read and understand the terms of a contract before he or she affixes his or her signature to it.” Even though the form could be clearer, Barney had a duty to understand what he was signing and could not claim ignorance of the law as a defense.

Practice Implications

This decision reinforces that parties cannot escape contractual obligations by claiming ignorance of legal consequences. For family law practitioners, it underscores the importance of thoroughly explaining the legal effects of paternity documents to clients. The court noted that the issue of Mackley’s standing became moot due to the valid denial, but referenced its companion decision in Castro v. Lemus establishing that alleged fathers have standing under the UUPA to challenge presumed paternity.