## Facts

- Homeowners living near natural-gas drilling operations sued multiple drilling-related entities for personal injury and property damage allegedly caused by pollutants from drilling and hydraulic fracturing activities.
- After initial disclosures under Colorado Rule of Civil Procedure 26, defendants sought a modified case-management order requiring early proof of exposure, injury, and causation before full discovery.
- The trial court entered a Lone Pine-type order requiring, within a fixed period, expert opinions and medical records showing (1) exposure to toxins from defendants’ operations, (2) specific causation connecting identified toxins to each plaintiff’s injuries, and (3) identification and quantification of property contamination attributable to defendants.
- Plaintiffs submitted photographs, medical records, test data, and a physician affidavit stating further investigation was warranted, but did not provide expert opinions establishing exposure to specific toxins or specific causation.
- The trial court dismissed the case with prejudice for noncompliance.
- The court of appeals reversed, concluding Colorado procedure did not authorize such orders, and the state supreme court granted review.

## Issues

1. Whether Colorado trial courts may, under the Colorado Rules of Civil Procedure, require plaintiffs to present prima facie evidence of exposure, injury, and causation as a precondition to full discovery through a Lone Pine-type case-management order.
2. Whether dismissal with prejudice may be imposed for failure to satisfy that pre-discovery evidentiary requirement.

## Decision

- The Colorado Supreme Court affirmed the court of appeals.
- The court held the Colorado Rules of Civil Procedure do not authorize a case-management order that conditions full discovery on a plaintiff’s pre-discovery prima facie evidentiary showing.
- The court concluded the trial court exceeded permissible case-management authority by creating a summary-judgment-like filter outside the rules’ established mechanisms.
- The dismissal with prejudice was reversed, and the case was remanded for further proceedings under ordinary discovery and dispositive-motion practice.

## Legal Principles

- Rule 16 case management must operate within, and cannot modify or conflict with, the Colorado Rules of Civil Procedure.
- Courts may not create pre-discovery evidentiary screening devices that function as substitutes for Rule 12(b)(5) motions to dismiss or Rule 56 summary judgment.
- Inherent authority to control dockets and manage litigation does not permit procedures that effectively amend the civil rules or alter parties’ discovery rights and obligations.
- Any adoption of Lone Pine-style preconditions to discovery in Colorado requires formal rulemaking, not ad hoc case-management innovation.

## Conclusion

Colorado trial courts lack authority to require toxic-tort plaintiffs to produce prima facie expert evidence of exposure and specific causation before full discovery, and they may not dismiss with prejudice for failing to meet such a pre-discovery burden imposed by a Lone Pine-type order.


Antero Res. Corp. v. Strudley, 2015 CO 26, 347 P.3d 149 (Colo. 2015)