## Facts

- Barbara Head was injured at work in Oklahoma when a reflector/shade from a hanging fluorescent light fixture fell from its channel and struck the side of her head as a co-worker released one end to check an electrical problem.
- Head did not lose consciousness but later reported headaches, dizziness, and occasional blackouts; she took medical leave and was later terminated.
- Head sued the fixture manufacturer in a diversity products-liability action, alleging a design defect in the quarter-turn fastener that secured the reflector in the grooved channel.
- To support a claim of permanent neurological injury, Head presented a neurologist, Dr. Michael Haugh, who testified that conventional clinical tests were normal except for a “topographical brain-map” test (computerized analysis of brain electrical activity).
- Dr. Haugh attributed Head’s condition to post-concussive syndrome based largely on the brain-mapping results.
- On cross-examination, Dr. Haugh acknowledged the technique was controversial and not accepted by the American Academy of Neurology.
- The district court permitted a late amendment to the pretrial order, allowed Dr. Haugh to testify (including on design and causation), admitted the brain-mapping evidence over objection, and the jury awarded $100,000 for permanent injury.

## Issues

1. Whether the evidence required a directed verdict for the manufacturer on defect and causation under Oklahoma products-liability standards.
2. Whether the district court abused its discretion by permitting a late amendment to the pretrial order.
3. Whether the district court abused its discretion by allowing the neurologist to offer opinions allegedly outside his expertise.
4. Whether the district court erred by admitting topographical brain-mapping results without a foundational showing under Federal Rule of Evidence 703 that the test is the type of data reasonably relied upon by neurologists.

## Decision

- The court affirmed the denial of a directed verdict, holding that the evidence permitted reasonable jurors to find defect and causation.
- The court found no abuse of discretion in allowing modification of the pretrial order under Rule 16(e).
- The court found no reversible error in permitting the challenged expert testimony within the trial court’s discretion over expert qualifications and scope.
- The court vacated the judgment and remanded for a new trial because the district court failed to address the foundational objection to the brain-mapping evidence and admitted it without the required Rule 703 inquiry.
- The error was not harmless because the brain-mapping test was the primary abnormal finding and a central basis for the permanent-injury award.

## Legal Principles

- A directed verdict is improper if, viewing the evidence favorably to the nonmovant, reasonable jurors could reach different conclusions on defect and causation.
- A pretrial order may be modified “to prevent manifest injustice,” and the decision is reviewed for abuse of discretion.
- Trial courts have broad discretion to determine expert qualifications and the permissible scope of expert testimony.
- Under Federal Rule of Evidence 703, an expert may base an opinion on facts or data only if they are of a type reasonably relied upon by experts in the relevant field.
- When a party challenges a novel or disputed scientific technique, the trial court must make an on-the-record foundational determination of reasonable reliance (and related reliability concerns) before admitting the evidence.

## Conclusion

The Tenth Circuit left intact the trial court’s rulings on liability sufficiency, pretrial-order modification, and general expert testimony, but vacated and remanded for a new trial because the court admitted controversial brain-mapping evidence without making the foundational findings required by Rule 703, and that evidentiary error likely affected the permanent-injury verdict.


Head v. Lithonia Corp., Inc., 881 F.2d 941 (10th Cir. 1989)