WMATA v. Nash-Flegler, 272 A.3d 1171

Plaintiff Albert Nash-Flegler slipped on ice while deboarding a Metro train at Deanwood station; WMATA had placed a single yellow warning cone on the platform, which plaintiff says he did not see.
Nash-Flegler sued WMATA for negligent maintenance (which the trial court granted summary judgment for WMATA) and for failure to warn (trial court denied summary judgment on sovereign-immunity grounds as to this claim).
WMATA filed an interlocutory appeal arguing the denial of sovereign immunity was immediately appealable and that sovereign immunity bars the failure-to-warn claim because the cone-placement decision implicated policy judgments.
The D.C. Court of Appeals considered (1) whether the denial of sovereign immunity is an appealable collateral order and (2) whether sovereign immunity applies to the failure-to-warn claim challenging placement of a single cone.
The court held the denial of WMATA’s sovereign-immunity defense is immediately appealable under the collateral order doctrine and affirmed the trial court’s denial of sovereign immunity for the failure-to-warn claim.
The court reasoned the record contains no evidence that policy, economic, or political judgments actually informed the employee’s decision to place one cone, and the act of placing a temporary cone is not by its nature fraught with policy considerations that would trigger sovereign immunity.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Is denial of WMATA's sovereign immunity immediately appealable under the collateral order doctrine?	Denial not effectively unreviewable later; Will and McNair suggest narrow collateral-order application.	Denial conclusively decides legal question; sovereign immunity is an immunity from suit and would be lost if review waited.	Appealable: collateral order doctrine satisfied; interlocutory appeal permitted.
Does sovereign immunity bar Nash-Flegler's failure-to-warn claim about placement of a single warning cone?	Cone may have been invisible; claim alleges an effective failure to warn, not a policy-driven decision; duty to warn where hazard not open and obvious.	Cone-placement decision is "susceptible to policy judgment" (e.g., avoid bottlenecks/trip hazards; preserve warning efficacy), so discretionary and immune.	Denied immunity: no record evidence of policy judgments; placement of a temporary cone not inherently fraught with public-policy considerations; immunity does not apply.
Does the cone's visibility determine entitlement to sovereign immunity?	Trial court suggested visibility could affect immunity.	WMATA argued visibility aside, the dispositive question is whether the decision involved policy judgment.	Visibility is not the controlling test; the dispositive inquiry is whether the nature of the decision is inherently policy-laden and whether policy judgments actually informed it.

Abdulwali v. WMATA, 315 F.3d 302 (D.C. Cir. 2003) (held denial of WMATA immunity in a failure-to-warn suit was immediately appealable and applied discretionary-function analysis)
KiSKA Constr. Corp. v. WMATA, 167 F.3d 608 (D.C. Cir. 1999) (recognized immediate appealability of WMATA sovereign-immunity determinations)
Barksdale-Showell v. WMATA, 965 A.2d 16 (D.C. 2009) (WMATA not immune where record lacked policy rationale for failing to warn)
Cope v. Scott, 45 F.3d 445 (D.C. Cir. 1995) (location and type of signs may be rooted in engineering/aesthetic considerations and not necessarily discretionary for immunity)
Will v. Hallock, 546 U.S. 345 (2006) (explained limits of collateral-order doctrine and that only interests preventing trial that imperil substantial public interests justify immediate appeal)
United States v. Gaubert, 499 U.S. 315 (1991) (discretionary-function exception protects policy-grounded government actions from tort liability)