Utah Court of Appeals
Must defendants preserve inherent improbability claims in the trial court? State v. Mayorga Explained
Summary
Mayorga was convicted of unlawful firearm possession, aggravated assault with a firearm, and criminal mischief based primarily on his ex-girlfriend’s testimony about incidents in a hotel room and car. The jury acquitted him on other charges including aggravated kidnapping and additional assault charges. Mayorga appealed claiming the evidence was insufficient and that the victim’s testimony was inherently improbable.
Analysis
In State v. Mayorga, the Utah Court of Appeals addressed an important preservation issue regarding challenges to witness testimony under the inherent improbability doctrine established in State v. Robbins.
Background and Facts
Mayorga was convicted of three crimes: unlawful firearm possession, aggravated assault with a firearm, and criminal mischief. The charges arose from incidents involving Mayorga and his ex-girlfriend Elise, including threatening her with a gun in a hotel room and breaking her car radio. While the jury convicted on these three counts, they acquitted Mayorga on other charges including aggravated kidnapping and additional assault charges.
Key Legal Issues
Mayorga raised two primary arguments on appeal: (1) the evidence was insufficient to support the convictions, and Elise’s testimony was “inherently improbable” under State v. Robbins; and (2) the trial court should have given a specific unanimity instruction regarding the aggravated assault charge since multiple acts were described.
Court’s Analysis and Holding
The court held that Mayorga failed to preserve his Robbins claim for appellate review. While Mayorga made general sufficiency arguments and used the phrase “inherently improbable” in his post-trial motion, he never specifically argued that Elise’s testimony should be disregarded due to inherent improbability, nor did he cite Robbins or similar case law. The court emphasized that a Robbins claim “introduces a new legal theory” distinct from general insufficiency challenges.
On the preserved sufficiency challenge, the court found adequate evidence supported all three convictions when viewing the evidence in the light most favorable to the State. Regarding the unanimity instruction, the court concluded Mayorga demonstrated no prejudice because the multiple assaultive acts were largely undifferentiated and occurred as part of the same continuous course of conduct.
Practice Implications
This decision clarifies that preservation requirements apply separately to Robbins inherent improbability claims. Defense counsel cannot rely on general insufficiency arguments to preserve these specialized challenges. When testimony appears inherently improbable, practitioners must specifically raise this theory with appropriate citations to Robbins and related precedent in the trial court. The ruling also demonstrates how courts analyze prejudice in unanimity instruction cases, considering whether reasonable jurors would likely differentiate between similar acts occurring in the same timeframe and location.
Case Details
Case Name
State v. Mayorga
Citation
2024 UT App 182
Court
Utah Court of Appeals
Case Number
No. 20230464-CA
Date Decided
December 12, 2024
Outcome
Affirmed
Holding
A defendant’s failure to preserve an inherent improbability claim under State v. Robbins precludes appellate review of that claim, and sufficient evidence supports convictions when victim testimony provides evidence of each element of the charged offenses.
Standard of Review
Correctness for trial court’s denial of motions for directed verdict and to arrest judgment; correctness for claims of plain error and ineffective assistance of counsel
Practice Tip
When challenging witness testimony as inherently improbable under State v. Robbins, defendants must specifically raise this legal theory in the trial court with citation to relevant case law, as general insufficiency arguments do not preserve Robbins claims for appeal.
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