## Facts

- Billi Jo Smallwood lived with her husband and three minor children in base housing at Fort Campbell, a U.S. Army installation.
- One night, neighbors alerted authorities that the Smallwood residence was on fire.
- Emergency personnel found Smallwood, her husband, and their youngest child outside the home; the other two children remained inside and died in the fire.
- Smallwood suffered second-degree burns.
- An Army Criminal Investigation Division (CID) agent observed that the family vehicle had been vandalized: the tires were flattened and words were written on the vehicle.
- A knife was found on a desk inside the home and was collected as evidence.
- Smallwood was indicted for maliciously damaging and destroying, by means of fire, property owned by the federal government, and for the same offense with the added allegation that deaths resulted.
- For trial, the government sought to offer toolmark testimony from Kristin Gerber, who planned to compare test marks made by the seized knife with marks on the vehicle’s slashed tires and to opine that the knife was the tool used.
- Smallwood moved to exclude Gerber’s testimony under Federal Rule of Evidence 702 and Daubert, arguing that toolmark comparison is highly subjective, depends heavily on the examiner, and that Gerber’s training and experience focused on firearms rather than knife marks in tires.
- At a Daubert hearing, Smallwood also challenged whether Gerber’s work could be meaningfully tested in court because Gerber repeatedly stated that photographs used in questioning did not show what she observed through a comparison microscope.

## Issues

1. Whether, under Federal Rule of Evidence 702 and Daubert, the government’s toolmark examiner could testify that toolmarks in the slashed tires matched test marks made by the knife recovered from the home.
2. Whether the examiner’s limited knife-specific training and limited prior work with knife marks in tires required exclusion, or instead went to weight and the proper scope of any opinion.

## Decision

- The court denied Smallwood’s motion to exclude Gerber’s toolmark testimony.
- The court found that toolmark comparison methods commonly used in firearms/toolmark work can satisfy Rule 702’s reliability threshold, even though they involve examiner judgment.
- The court recognized meaningful limits in this case—especially the examiner’s limited experience with knife-to-tire comparisons—and indicated those limits were proper subjects for cross-examination and for controlling how strongly the opinion could be stated at trial.

## Legal Principles

- Federal Rule of Evidence 702 permits opinion testimony by a qualified witness if it will help the jury, is based on sufficient facts or data, is the product of reliable principles and methods, and reflects a reliable application of those methods to the case.
- Under Daubert (and Kumho Tire for technical fields), the trial judge acts as gatekeeper and evaluates reliability and fit; the court does not decide which side’s view is correct.
- Reliability may be evaluated using flexible considerations such as testability, peer review, known or potential error rates, standards controlling the work, and general acceptance, with the mix depending on the field and the task.
- In pattern-comparison disciplines, limits in training, experience, documentation, or the ability to show the basis for a comparison can affect the strength and wording of an opinion, and may justify restricting testimony even when some comparison testimony is allowed.
- Weaknesses in an otherwise admissible expert opinion are typically handled through cross-examination, competing proof, and careful control of the scope and certainty of what the witness may claim.

## Conclusion

United States v. Smallwood addressed whether the government could use toolmark comparison testimony to connect a knife found in the defendant’s home to slashed tires on the family vehicle in an arson-deaths prosecution. Applying Rule 702 and Daubert, the court allowed the toolmark examiner to testify about her comparison and conclusions, while recognizing that the subjective nature of the method and the examiner’s limited knife-specific experience were significant limitations to be tested at trial and managed through the permitted scope and phrasing of the opinion.


United States v. Smallwood, 2010 WL 4168823 (2010)