CROSSOVER: Rule 91a vs. Plea to the Jurisdiction: Automatic Discovery Stay Applies When Immunity Is Challenged—Mandamus Available to Vacate Orders Entered During Stay

City of Houston v. Castillo, 14-25-00351-CV, March 12, 2026.

On appeal from the 190th District Court Harris County, Texas.

Synopsis

A plaintiff pleading a Texas Tort Claims Act (TTCA) motor-vehicle waiver need not preemptively “plead around” the TTCA’s emergency/911 exceptions unless the petition’s own allegations plausibly implicate those exceptions. Separately, a Rule 91a motion that challenges governmental immunity is treated as a jurisdictional challenge for Chapter 51 purposes, triggering the automatic stay under Tex. Civ. Prac. & Rem. Code § 51.014(b). Orders entered during that stay—such as discovery orders—are vulnerable to mandamus and must be vacated.

Relevance to Family Law

Family-law litigators increasingly encounter governmental entities and immunity-adjacent issues in SAPCRs and divorces: police conduct at exchanges, CPS-related vehicle incidents, county vehicles involved in collisions with parties, and subpoenas/discovery directed at governmental custodians. This opinion matters because it (1) tightens pleading expectations when you sue a governmental unit (or when the other side does), and (2) provides a tactical “stop button” on trial-court activity—especially discovery—once a governmental unit frames its attack as an immunity/jurisdiction challenge, even if styled as a Rule 91a motion. In high-conflict custody litigation where discovery tempo is a strategic lever, understanding when proceedings are automatically stayed—and how to unwind orders entered during the stay—can materially change leverage and sequencing.

Case Summary

Fact Summary

Castillo alleged she was driving northbound on Main Street when a City of Houston employee (identified in the pleadings as “Officer Franklin”) disregarded traffic signals at an intersection and struck her vehicle, causing injury. The City responded with a Rule 91a motion to dismiss, arguing that Castillo’s petition was defective because it did not affirmatively negate TTCA exceptions to the motor-vehicle waiver—specifically, the emergency and 911-response exceptions in Tex. Civ. Prac. & Rem. Code § 101.021(1)(A). The City also attempted to leverage a sentence in Castillo’s petition suggesting that, “on the face,” the officer “would be protected” by official immunity, characterizing it as a judicial admission that eliminated the City’s TTCA exposure.

While the interlocutory appeal was pending, the trial court signed a discovery order. The City sought mandamus relief, contending that the appeal triggered the statutory automatic stay of trial-court proceedings under Tex. Civ. Prac. & Rem. Code § 51.014(b) because the Rule 91a motion—though not labeled as a plea to the jurisdiction—was substantively an immunity/jurisdiction challenge.

Issues Decided

• Whether a plaintiff must affirmatively negate TTCA exceptions (including emergency/911 exceptions) in the petition to survive a Rule 91a dismissal, even when the pleaded facts do not plausibly implicate those exceptions.
• Whether a statement in the petition about an officer “would be” protected by official immunity constitutes a binding judicial admission defeating TTCA liability.
• Whether a Rule 91a motion that challenges governmental immunity constitutes a jurisdictional challenge that triggers the automatic stay under Tex. Civ. Prac. & Rem. Code § 51.014(b).
• Whether mandamus relief is available to vacate a discovery order entered during the automatic stay.

Rules Applied

The court’s analysis turned on the intersection of pleading sufficiency, immunity doctrine, and Chapter 51 interlocutory-appeal procedure:

• TTCA motor-vehicle waiver and exceptions: Tex. Civ. Prac. & Rem. Code § 101.021(1)(A) (waiver for injury arising from operation/use of motor-driven vehicle), with emergency/911-response limitations.
• Pleading burden re: TTCA exceptions: Rattray v. City of Brownsville, 662 S.W.3d 860, 868 (Tex. 2023) (a plaintiff need not negate all exceptions; only when the petition “plausibly implicate[s]” an exception must the plaintiff plead why it does not apply).
• Judicial admissions standard: A judicial admission must be “a clear, deliberate, and unequivocal assertion of fact.” Wilson v. Fleming, 669 S.W.3d 450, 461 (Tex. App.—Houston [14th Dist.] 2021), aff’d on other grounds, 694 S.W.3d 186 (Tex. 2024).
• Immunity determinations are legal questions: Stephen F. Austin State Univ. v. Flynn, 228 S.W.3d 653, 657 (Tex. 2007).
• Rule 91a + immunity = Chapter 51 jurisdictional challenge: San Jacinto River Auth. v. Medina, 627 S.W.3d 618, 621 (Tex. 2021); City of Dallas v. Sanchez, 494 S.W.3d 722, 725 (Tex. 2016) (per curiam); and the Fourteenth Court’s own precedent, including City of Houston v. Boodoosingh, 693 S.W.3d 894 (Tex. App.—Houston [14th Dist.] 2024, no pet.).
• Automatic stay during interlocutory appeal by governmental unit: Tex. Civ. Prac. & Rem. Code § 51.014(b).
• Mandamus to correct orders entered during stay: the order is an abuse of discretion and lacks an adequate appellate remedy. See In re Univ. of the Incarnate Word, 469 S.W.3d 255, 260 (Tex. App.—San Antonio 2015, orig. proceeding).

Application

On the Rule 91a dismissal, the court treated the case as a pleading-sufficiency fight framed by Rattray. Castillo alleged a classic TTCA motor-vehicle scenario: injury arising from a City employee’s negligent operation of a motor vehicle. Critically, her petition did not plead facts suggesting an emergency response, a 911 call, lights-and-sirens operation, or any other circumstance that would plausibly trigger the emergency/911 exceptions. Under Rattray, that meant Castillo was not required to go further and affirmatively negate exceptions that were not teed up by her own allegations. The City’s attempt to impose a categorical “negate every exception in the petition” burden was rejected as inconsistent with supreme court guidance and the Fourteenth Court’s prior decision in Polk.

The City’s “judicial admission” theory also failed because it tried to convert a legally loaded characterization (“would be protected by official immunity”) into a binding admission. The court emphasized two defects: (1) immunity is a question of law, not a factual concession suitable for judicial-admission treatment; and (2) the phrasing (“would be”) lacked the clarity and unequivocal character required for an admission that destroys a claim.

On the stay/mandamus issue, the court took a functional approach. The City’s appeal was from the denial of a Rule 91a motion, but the substance of that motion was an immunity-based attack—i.e., a jurisdictional challenge. Under Medina and Sanchez, that categorization brings the appeal within Chapter 51 and triggers the statutory automatic stay of trial-court proceedings under § 51.014(b). Because the discovery order was entered while the stay was in place, the trial court acted outside permissible authority; mandamus was the appropriate remedy to compel vacatur, since allowing discovery to proceed (or leaving the discovery order intact) would undermine the very protection the stay is designed to provide.

Holding

The court affirmed the trial court’s denial of the City’s Rule 91a motion to dismiss. Castillo’s petition sufficiently pleaded a TTCA waiver by alleging injury arising from the negligent operation/use of a motor-driven vehicle, and she was not required to affirmatively negate the emergency/911 exceptions absent allegations that plausibly implicated them.

The court also rejected the City’s judicial-admission argument, holding that the petition’s statement about the officer “would be” protected by official immunity was neither a clear, deliberate, unequivocal assertion of fact nor an admissible concession on what is ultimately a legal question.

Finally, the court conditionally granted mandamus relief and ordered the trial court to vacate its discovery order entered during the statutory automatic stay. A Rule 91a motion challenging governmental immunity triggers § 51.014(b)’s stay; proceedings conducted during the stay are subject to correction by mandamus.

Practical Application

In family law, you rarely litigate a pure TTCA motor-vehicle case inside the divorce/SAPCR itself—but you frequently collide with the same procedural machinery: governmental parties, immunity defenses, and discovery sought from or about governmental actors. This opinion supplies two high-value tactics.

First, if you represent the claimant side in a related civil action (or third-party claim) against a city/county entity arising out of an incident entangled with a family case—think police involvement at an exchange, transport incidents, or county-employee driving—your pleadings can be streamlined: plead the waiver facts cleanly, and do not volunteer “emergency response” details unless you can also plead why the exception does not apply. Conversely, if you represent the governmental unit (or an aligned party), this case underscores that you may not win a pleadings-only dismissal by merely pointing to unpleaded TTCA exceptions; you will likely need evidence via plea to the jurisdiction once the exception is actually in play.

Second, for litigators managing parallel proceedings, the automatic stay holding is the bigger lever. When a governmental unit perfects an interlocutory appeal on immunity grounds—even through a Rule 91a vehicle—trial-court proceedings halt by statute. That creates immediate sequencing consequences: depositions, subpoenas, and hearings can become voidable, and orders signed during the stay are prime mandamus targets. In custody litigation where one side is using aggressive discovery or expedited settings to force concessions, the stay can neutralize momentum if a governmental unit is properly in the case and has teed up an appealable immunity issue.

Checklists

Checklists

Drafting a TTCA Petition That Survives Rule 91a

• Plead the statutory waiver facts with specificity (operation/use of a motor-driven vehicle; employee acting in scope; causation and damages).
• Avoid gratuitous facts that “plausibly implicate” an exception (emergency response, 911 dispatch, pursuit, lights/sirens) unless you can also plead why the exception does not apply.
• Keep legal conclusions about immunity out of the petition (do not concede “official immunity applies” in narrative form).
• If you must address an exception, plead the negation facts affirmatively (e.g., no emergency, no compliance with statutory criteria, no good-faith emergency operation).

Defending a Governmental Unit: Choosing the Right Vehicle

• Evaluate whether the challenge is pleadings-only (Rule 91a) or requires evidence (plea to the jurisdiction with evidence).
• If relying on an exception (emergency/911), develop the evidentiary record early (CAD/dispatch logs, dashcam/bodycam, policies, witness statements).
• Do not assume you can force dismissal by arguing the plaintiff failed to negate exceptions not implicated by the petition.
• Consider the appellate/stay implications when choosing between Rule 91a and a plea to the jurisdiction.

Enforcing the Section 51.014(b) Automatic Stay (and Unwinding Violations)

• Upon filing/perfecting the interlocutory appeal, notify the trial court in writing of the § 51.014(b) stay and request that all settings be cancelled.
• Object immediately to any discovery activity or orders during the stay; create a clear record.
• If an order is signed during the stay, pursue mandamus promptly seeking vacatur.
• Audit the docket for “administrative” orders that may still constitute prohibited proceedings (discovery orders, sanctions, enforcement mechanisms).

Family-Law Parallel-Proceeding Strategy (Custody/Divorce + Government Actor)

• Map whether a governmental unit is a party or is being pulled in through claims that could trigger immunity defenses.
• Anticipate timing: an immunity appeal can freeze trial-court activity and disrupt temporary-orders or discovery calendars in related cases.
• If you need governmental discovery, plan around the possibility of a stay (seek non-governmental sources; preserve evidence early).
• If opposing counsel is attempting discovery during a stay, consider mandamus as a practical enforcement tool—not merely a threat.

Citation

City of Houston v. Castillo, No. 14-25-00351-CV, ___ S.W.3d ___ (Tex. App.—Houston [14th Dist.] Mar. 12, 2026, mem. op.).

Full Opinion

Read the full opinion here

Family Law Crossover

This decision is “weaponizable” in family litigation primarily as a procedural disruptor and a discovery-control tool. If a governmental unit is in the case—or is brought in via a third-party claim or related civil action—and it frames its immunity attack through Rule 91a (or any vehicle treated as a jurisdictional challenge), § 51.014(b) can slam the brakes on trial-court proceedings. That can freeze discovery that was pressuring your client, invalidate orders entered during the stay via mandamus, and force opposing counsel to litigate sequencing and jurisdiction before merits—often changing settlement dynamics around temporary orders, attorney’s fees, and custody evaluations.

On the pleading side, Castillo also cautions family-law practitioners who draft collateral petitions (or advise referral counsel) not to plead themselves into an exception. In contentious cases involving police at exchanges or CPS/constable transport, it is tempting to narrate “emergency” facts for rhetorical punch. Doing so may “plausibly implicate” TTCA exceptions and shift the burden back onto the plaintiff to plead negation—handing the defense an early dismissal pathway that Castillo otherwise forecloses on a clean waiver pleading.

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