United States v. Hernandez

United States Court of Appeals for the Tenth Circuit · 2024 · Evidence

Evidenceexpert testimonyRule 702Daubertfire investigationNFPA 921plain errorcredibility testimony

Facts

A fire at a mobile home killed Hernandez's mother and grandmother. Emergency responders heard both victims say Hernandez had poured gasoline on them and lit them on fire, while Hernandez later told police the fire started accidentally when gasoline ignited while he was smoking. Fire investigator Gene Wheat interviewed witnesses, examined and photographed the scene, and formed opinions that the fire originated near the breezeway, was likely caused by ignition of an accelerant, and that it is difficult to light gasoline with a cigarette. The mobile home was heavily damaged, and Wheat returned the next day to photograph the remains without a warrant.

Issue

Did the district court abuse its discretion by admitting Wheat's expert fire-origin testimony, plainly err by not sua sponte striking Wheat's statement that he did not believe Hernandez's explanation, and err by admitting photographs obtained after Wheat entered the fire-damaged mobile home scene without a warrant?

Rule

A district court has broad discretion to admit expert testimony if it satisfies Federal Rule of Evidence 702 and is reliable under Daubert; compliance with NFPA 921 is relevant but its provisions are flexible recommendations rather than strict requirements. Unobjected-to allegedly improper credibility testimony is reviewed for plain error, and reversal requires a reasonable probability that the result would have been different absent the error. A warrant is not required to enter fire-damaged property when, considering the type of property, extent of damage, prior and continued use, and efforts to secure the premises, no reasonable privacy interest remains in the ash and ruin.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

After a warehouse fire in Tulsa, prosecutors call fire investigator Dana Mercer to testify that the fire originated near a loading dock and was likely fueled by an ignitable liquid. Mercer interviewed employees first, then inspected burn patterns, electrical wiring, and fuel containers, but did not perform arc mapping. Defense counsel moves to exclude the testimony solely because Mercer did not follow every recommendation in NFPA 921.

How should the court most likely rule?

Explanation. The majority treated NFPA 921 as relevant but flexible guidance, not a mandatory checklist. A district court has broad discretion to admit expert testimony if it is based on sufficient facts or data, reliable principles and methods, and a reasonable application of those methods. Here, interviewing witnesses, inspecting physical evidence, and analyzing the scene can support reliability even without perfect compliance with NFPA 921. (Derived from United States v. Hernandez (n.d.).)