## Facts

- A Greyhound bus driven by Robert L. Schlagenhauf collided with the rear of a tractor-trailer, and bus passengers filed a federal diversity negligence action against multiple defendants, including Schlagenhauf and the tractor-trailer interests.
- All defendants denied negligence; cross-claims alleged the collision was caused by the tractor-trailer’s negligence, while the tractor-trailer defendants alleged negligence by Greyhound and Schlagenhauf.
- Contract Carriers asserted (via a filing treated as part of its answer) that Schlagenhauf was not mentally or physically capable of operating the bus at the time of the accident.
- National Lead alleged Greyhound and Schlagenhauf permitted him to drive despite a known visual deficiency.
- Contract Carriers and National Lead moved under Federal Rule of Civil Procedure 35(a) to compel Schlagenhauf to undergo multiple examinations (internal medicine, ophthalmological, neurological, and psychiatric).
- The district court ordered Schlagenhauf to submit to the requested examinations over his objection.
- Schlagenhauf sought mandamus in the court of appeals to set aside the order; the court of appeals denied relief.
- The Supreme Court granted certiorari to address mandamus and the proper application of Rule 35(a)’s “in controversy” and “good cause” requirements.

## Issues

1. Whether mandamus is available to review whether a district court exceeded its authority in ordering examinations under Rule 35(a).
2. Whether Rule 35(a) permits compelled mental and physical examinations of a defendant.
3. What showing is required to establish that a party’s condition is “in controversy” and that “good cause” exists, particularly when multiple examinations are sought.

## Decision

- The Court held that mandamus was an appropriate means to review whether the district court exceeded its power under Rule 35(a), given the substantial and novel question regarding the scope of the Rule.
- The Court held that Rule 35(a) may apply to a defendant because the Rule authorizes examinations of “a party,” not only plaintiffs.
- The Court ruled that Rule 35(a)’s “in controversy” and “good cause” requirements demand a specific, affirmative showing for each examination and are not satisfied by conclusory allegations or general relevance.
- The Court concluded that the district court’s broad order was not adequately supported as to the full range of requested examinations and therefore required reconsideration under the proper standard.
- The Court reversed the court of appeals to the extent it refused to treat the order as an excess of power and directed reconsideration consistent with the Court’s interpretation of Rule 35(a).

## Legal Principles

- Mandamus is not a substitute for appeal, but it may be used to correct a lower court’s usurpation or excess of judicial power, including in important disputes over the meaning of the Federal Rules.
- Rule 35(a) permits a court to order a mental or physical examination of any party, including a defendant, when the Rule’s prerequisites are satisfied.
- The “in controversy” and “good cause” requirements are substantive limits; they require a concrete, examination-specific showing supported by facts, not bare allegations in pleadings.
- Trial courts must apply Rule 35(a) in a discriminating manner, assessing separately whether each requested examination is justified by the record and the needs of the case.

## Conclusion

The Court permitted mandamus to review a Rule 35 order raising an important question of judicial authority and held that compelled examinations—including of a defendant—may be ordered only upon a specific factual showing that the condition is genuinely in controversy and that good cause supports each particular examination.


Schlagenhauf v. Holder, 379 U.S. 104 (1964)