CROSSOVER: Rule 193.6 Reversal: Undisclosed Trial Evidence Can Force a New Trial in Texas Cases, Including Family-Law Bench Trials

Juan Gasca v. Marcque Keller, 05-24-00724-CV, May 27, 2026.

On appeal from County Court at Law No. 5, Dallas County, Texas

Synopsis

Texas Rule of Civil Procedure 193.6 is not a technicality; it is a mandatory exclusion rule. In Gasca v. Keller, the Dallas Court of Appeals reversed a bench-trial judgment because the trial court admitted untimely disclosed evidence supporting a late-added claim, and that error probably caused rendition of an improper judgment.

For Texas litigators, including family-law trial lawyers, the message is straightforward: if an opponent tries to prove a newly pleaded claim with evidence not timely disclosed in discovery, exclusion should be automatic unless that party carries the burden to establish good cause or lack of unfair surprise or unfair prejudice.

Relevance to Family Law

Although Gasca arose from a landlord-tenant dispute, its procedural holding translates directly into Texas family-law practice. Divorce, SAPCR, modification, enforcement, reimbursement, waste, tracing, and attorney’s-fee disputes frequently turn on documents, summaries, account statements, business records, valuations, and damage models that are produced late or not supplemented at all. This opinion confirms that Rule 193.6 applies with full force in bench trials, which matters because family cases are often tried to the court and trial judges sometimes admit late material on the assumption that they can simply “give it the weight it deserves.” Gasca is a reminder that when the evidence was not timely disclosed, admissibility—not weight—is the first issue, and failure to enforce the rule can produce reversal and a new trial.

Case Summary

Fact Summary

The underlying case was a landlord-tenant dispute that evolved into competing statutory and contract claims. Keller sued Gasca under the Property Code based on alleged failure to repair and alleged landlord retaliation. Gasca answered and asserted counterclaims for breach of lease, later adding claims for unpaid rent and repair damages.

The critical appellate issue developed late. About two weeks before the bench trial, Keller added a new claim for wrongful retention of his security deposit. Gasca responded by filing a motion to exclude evidence not timely produced in discovery, arguing Keller’s disclosures and exhibit production were incomplete and delayed and that Keller was attempting trial by ambush. According to the opinion, several exhibits were not disclosed until two days before trial or even on the day of trial. Keller’s principal response was that many of the materials had been produced in related eviction litigation.

The trial court initially indicated at least some of the late-produced exhibits would be excluded, but later admitted the exhibits during Keller’s case-in-chief over Gasca’s Rule 193.6 objection. After the bench trial, the court rendered judgment for Keller on his Property Code claims, awarded statutory penalties, attorney’s fees, and costs, and denied Gasca’s claims. On appeal, Gasca challenged, among other things, the admission of the untimely disclosed evidence.

Issues Decided

• Whether Texas Rule of Civil Procedure 193.6 required exclusion of evidence that was not timely disclosed in discovery.
• Whether the party offering the evidence established either good cause or lack of unfair surprise or unfair prejudice sufficient to avoid automatic exclusion under Rule 193.6.
• Whether admission of the undisclosed evidence was reversible error because it probably caused rendition of an improper judgment under Texas Rule of Appellate Procedure 44.1(a).
• Whether the late-disclosed evidence materially supported a claim added shortly before trial, making the error harmful.

Rules Applied

The court relied principally on the following authorities:

• Texas Rule of Civil Procedure 193.1 and 193.5, which impose the duty to make, amend, and supplement discovery responses in a timely manner.
• Texas Rule of Civil Procedure 193.6(a), which bars a party from introducing evidence not timely disclosed unless the court finds good cause or lack of unfair surprise or unfair prejudice.
• Texas Rule of Civil Procedure 193.6(b), which places the burden on the offering party to establish the exception and requires the finding to be supported by the record.
• Texas Rule of Appellate Procedure 44.1(a), under which an evidentiary error warrants reversal if it probably caused rendition of an improper judgment.
• Lopez v. La Madeleine of Tex., Inc., 200 S.W.3d 854, 860 (Tex. App.—Dallas 2006, no pet.), recognizing that Rule 193.6 is mandatory and exclusion is automatic absent the required showing.
• Jackson v. Takara, 675 S.W.3d 1, 6 (Tex. 2023), confirming that the Rule 193.6 record may include evidence or undisputed representations of counsel.
• The court also cited its own precedent emphasizing that the good-cause exception is narrow and is meant to address difficult or impossible circumstances, not ordinary noncompliance.

Application

The appellate court treated the Rule 193.6 issue as dispositive. Its analysis began with the mandatory structure of the rule: if evidence was not timely disclosed, the evidence comes out unless the proponent affirmatively proves one of the two exceptions. That burden never shifts. The trial court does not have broad equitable discretion to admit the evidence simply because the case is being tried to the bench or because the judge believes the opponent can cross-examine around the problem.

The record, as described by the court, showed that Keller added a security-deposit claim shortly before trial and relied on exhibits that had not been timely disclosed in the discovery governing the county-court case. Keller’s principal justification—that the materials had been produced in separate eviction litigation—did not satisfy Rule 193.6 on this record. The operative question was whether the evidence had been timely disclosed in the case being tried, and whether the proponent established good cause or lack of unfair surprise or unfair prejudice. The opinion indicates Keller did not carry that burden.

The court then moved from error to harm. That step is where the case becomes especially important for family-law litigators. The Dallas court did not treat the evidentiary mistake as harmless merely because this was a bench trial. Instead, it focused on the function the late-disclosed evidence served in the judgment. Because the evidence supplied support for a claim that had itself been added only shortly before trial, admission of the material likely affected the judgment. That was enough to satisfy Rule of Appellate Procedure 44.1(a). In short, the combination of a late-added claim and late-disclosed supporting proof created a classic reversible-ambush scenario.

Holding

The court held that Rule 193.6 required exclusion of the untimely disclosed evidence unless Keller established either good cause or lack of unfair surprise or unfair prejudice, and the record did not support such an exception. Because the trial court admitted the evidence over objection, it erred.

The court further held that the error was harmful. The undisclosed evidence supported a newly added security-deposit claim and therefore probably caused rendition of an improper judgment. On that basis, the Dallas Court of Appeals reversed the judgment and remanded the case for a new trial.

Practical Application

For family-law litigators, Gasca should be integrated immediately into both trial preparation and appellate preservation strategy. In divorce cases, late-produced bank records, QuickBooks exports, appraisals, business valuations, reimbursement summaries, and tracing exhibits are often offered to support claims or defenses that crystallize only near trial. In custody litigation, the same problem appears with social-media extractions, medical records, school records, therapist materials, and “chronologies” assembled just before trial. Gasca provides a clean framework: if the evidence was not timely disclosed in response to written discovery or required supplementation, object under Rule 193.6, force the proponent to establish the exception on the record, and insist on a ruling tied to the rule’s specific standards.

The case is particularly useful in bench trials, where lawyers sometimes relax their evidentiary discipline based on the assumption that reversible harm is harder to show. The opinion rejects that complacency. If the undisclosed exhibit supports a meaningful component of the judgment—such as a reimbursement claim, waste claim, separate-property tracing theory, retroactive child support calculation, attorney’s-fee request, or a conservatorship-related factual theory—the appellate harm argument remains very much alive.

From the proponent’s perspective, Gasca is equally important as a cautionary opinion. If you amend pleadings shortly before trial to add a new damages theory or claim for affirmative relief, you must immediately evaluate whether all supporting documents, calculations, and witnesses have been timely disclosed in the actual case. Production in a related protective-order action, a prior modification, a DFPS matter, or a separate business lawsuit will not necessarily save you. The safer practice is to supplement, identify the evidence expressly, and build a record of why the opposing party cannot claim surprise or prejudice.

Checklists

Preserving a Rule 193.6 Complaint at Trial

• Serve written discovery that requires disclosure of the categories of evidence you expect to matter at trial.
• Monitor amended and supplemental responses closely as trial approaches.
• Compare the opponent’s exhibit list, amended pleadings, and demonstratives against prior disclosures.
• File a written motion to exclude undisclosed or untimely disclosed evidence before trial when possible.
• Object again when the evidence is offered at trial; do not rely solely on the pretrial motion.
• Cite Rule 193.6(a) expressly and state that exclusion is automatic absent proof of an exception.
• Require the proponent to identify the precise discovery response in which the evidence was disclosed.
• Require the proponent to prove good cause or lack of unfair surprise or unfair prejudice on the record.
• Obtain a clear ruling.
• If the evidence is admitted, explain why it matters to a material claim or defense to support appellate harm.

Using Gasca Against Late-Added Family-Law Claims

• Scrutinize amended pleadings filed shortly before trial for new claims such as reimbursement, waste, offset, separate-property tracing, Epstein-type claims, attorney’s fees, or retroactive support.
• Match each new claim to the underlying documents, calculations, and witnesses needed to prove it.
• Determine whether those materials were actually disclosed in the family-law case, not just in a related proceeding.
• Move to strike or exclude evidence supporting the newly added claim if disclosure was late.
• Emphasize that late amendment plus late disclosure creates exactly the kind of unfair surprise Rule 193.6 is designed to prevent.
• If the evidence is central to the new claim, preserve the argument that admission probably caused rendition of an improper judgment.

Defending Against a Rule 193.6 Attack

• Supplement discovery immediately when new evidence, witnesses, or damage calculations become relevant.
• Do not assume document production in mediation, informal exchange, or a related case satisfies disclosure obligations.
• If you must rely on late-disclosed evidence, prepare a specific record establishing:
• why disclosure could not reasonably have been made earlier,
• when the information first became available,
• what the opposing party already knew,
• why the opponent is not unfairly surprised or prejudiced.
• Offer concrete facts, not conclusions, to support good cause or lack of surprise.
• Consider requesting a brief continuance if that will blunt a prejudice argument and preserve admissibility.
• Tie each exhibit to prior disclosures by bates number, supplementation date, or interrogatory response.

Bench-Trial Evidence Control in Family Cases

• Do not relax evidentiary objections merely because the judge is the factfinder.
• Object to late-produced summaries, demonstratives, and compilations the same way you would in a jury trial.
• Press the distinction between admissibility and weight.
• Remind the court that Rule 193.6 is mandatory and appellate courts will reverse bench-trial judgments when undisclosed evidence likely affected the result.
• Request findings of fact and conclusions of law where appropriate to help show the significance of the admitted evidence on appeal.

Appellate Framing After an Adverse Family-Law Judgment

• Identify each exhibit or witness admitted in violation of Rule 193.6.
• Show the absence of a record-based finding of good cause or lack of unfair surprise or unfair prejudice.
• Connect the challenged evidence to the particular relief awarded or denied.
• Emphasize whether the evidence supported a claim or theory added near trial.
• Use findings of fact, closing arguments, and the structure of the judgment to demonstrate harm.
• Frame the issue under both Rule 193.6 and Texas Rule of Appellate Procedure 44.1(a).

Citation

Juan Gasca v. Marcque Keller, No. 05-24-00724-CV, ___ S.W.3d ___, 2026 WL ___ (Tex. App.—Dallas May 27, 2026, no pet.) (mem. op.).

Full Opinion

Read the full opinion here

Family Law Crossover

This ruling can be weaponized effectively in Texas divorce and custody litigation because family cases routinely feature evolving claims and late-developed proof. If opposing counsel amends shortly before trial to assert reimbursement, hidden-asset allegations, separate-property tracing, business-valuation theories, waste, or a modified best-interest narrative, Gasca gives you a disciplined way to cut off the supporting proof if it was not timely disclosed. The strategic value is substantial: excluding a spreadsheet, valuation file, medical record set, social-media extraction, or expert backup material may not just weaken the opponent’s case—it may eliminate the evidentiary foundation for the late-added claim altogether.

The opinion is also useful offensively on appeal. Family-law practitioners often confront trial records in which the court admitted late-produced material on the theory that no jury was involved, so no real prejudice existed. Gasca undercuts that reasoning. If the undisclosed evidence supported a material component of the decree or final order, particularly one raised near trial, a bench-trial judgment remains vulnerable to reversal. In other words, this is not merely an evidence objection case; it is a retrial case. For the prepared family-law litigator, that makes Gasca a sharp procedural lever both at trial and on appeal.

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