Court of Appeal: Design Immunity Bars Failure-to-Warn Claims When Warnings Are in the Approved Plans

Tansavatdi v. City of Rancho Palos Verdes 123 Cal.App.5th 654 (Sept. 24, 2026)
Case Study

In 2023, the California Supreme Court left a question open in its decision in Tansavatdi I: whether design immunity applies if a government agency shows that the presence or absence of warning signs was part of the approved design.

The Court of Appeal has now held that when a government agency considers the warning signs for an alleged dangerous condition as part of the approval of a project’s design plans, the agency may rely on the design immunity defense under Government Code section 830.6. The protection only applies, though, if the government agency considered warnings about the property at issue, and included at least one such warning in the approved plans.

Background

In 2016, plaintiff Betty Tansavatdi’s minor son was killed when his bicycle collided with a truck making a turn at a City intersection. The City had approved the intersection’s design in 2009. She sued for dangerous condition of public property, alleging that the intersection lacked a bike lane and adequate warnings.

The case took a long road to this opinion. On the first summary judgment motion, the trial court held that design immunity barred the bike-lane theory but did not address the failure-to-warn theory. On appeal, the Second District held that design immunity does not necessarily bar a failure-to-warn theory, and it remanded. In Tansavatdi I (14 Cal.5th 639), the California Supreme Court held that design immunity “does not categorically preclude” failure-to-warn claims. It left open whether immunity applies when some warnings were part of the approved plans.

On remand to the trial court, on the second summary judgment motion the City showed that its warnings were considered and included in the approved design plans. Specifically, the City established that its approved plans for the intersection included the following warnings: 35 m.p.h. speed limit signs; an 8% steep grade sign; yellow chevron signs in the median; “traffic signal ahead” signs; a flashing yellow beacon in the median; right-turn lane striping; and two “RIGHT LANE MUST TURN RIGHT” signs. Plaintiff’s expert opined that more was needed, including a radar speed feedback sign and a flashing warning beacon system. But the trial court granted summary judgment for the City, and this second appeal followed.

The Court’s Holding

The Second District affirmed the trial court’s grant of summary judgment. Because a relevant warning was part of the approved design, design immunity applied. The appellate court rejected both of plaintiff’s arguments, namely, that design immunity does not reach failure-to-warn claims, and that different or additional warnings were required. Applying design immunity under these circumstances was necessary to fulfill the core purpose of the immunity, which is to prevent courts and juries from second-guessing discretionary governmental design decisions, including traffic engineering judgments about warnings.

What This Means for Government Agencies

• Put warnings in the plans. Warning signs and markings should be expressly addressed in the approved design, because if they are not in the plans and only later added in the field, their presence will not be relevant to the design immunity defense.
• Document the decision. The City’s motion only succeeded here because of records showing that the approving engineer considered the need for warning signs and markings at the intersection.
• Contrary expert opinions are not dispositive. When a warning was part of the approved design, this opinion forecloses the argument from experts that “more was needed.”
• Review current practices. Confirm that your project approval process involves analysis of the need for warnings on roadways and other public improvements and documents the inclusion of any warnings.

Conclusion

This opinion strengthens a key defense for government entities making hard tradeoffs in infrastructure design. The protection for design immunity is earned at the planning stage, so how warnings are considered and documented today will determine whether this defense is available in litigation years from now.

Meyers Nave’s Trial & Litigation group represents government entities in dangerous condition and design immunity matters. For questions about this decision or your agency’s plan-approval practices, contact us.

Note: This opinion was recently filed and may be subject to a petition for review.