Issue 162 - August 2025
NEWS: WORTHY
Risk Reduction in Public Planning: The Role of Warrants and Design Immunity
The session was informed by Dean’s expertise in navigating California’s government code section 830.6; this section shields public entities from liability when they follow approved design standards.
Dean began his presentation with warrants. Warrants are guidelines used to determine when specific traffic devices, like crosswalks, signals, and stop signs, are “warranted.” They’re based on state and national standards, and factor in traffic speed, pedestrian activity, crash history, and more to help create consistent, safe roadways.
After establishing the concept of warrants, Dean clarified the difference between basic and point warrants. Basic warrants outline the minimum requirements for consideration when mapping out traffic devices, like the number of pedestrians or the distance between marked crossings. Once these basic requirements are established, a location is further evaluated using point warrants, where additional, more specific factors help determine specific traffic device placement. “Warrants are not a substitute for an engineer’s judgment, nor do they equate to a dangerous condition,” he said. “A warrant merely indicates that the location should be further evaluated.”
Another essential resource imparted was the concept of design immunity—one of the strongest legal defenses available to public agencies. Design immunity is granted when a documented plan is pre-approved by either the city council, county board of supervisors, or an official with discretionary authority to make such approvals. These officials can include positions such as city engineers, traffic engineers, or other employees designated by public entity legislation, such as city codes and municipal codes.
Thorough documentation of the approval process is encouraged, as even small changes from approved designs can become points of litigation. Everything from detailed engineering drawings to annotated photos can serve as proof of approval. “Design immunity is broad, but it only works if it’s backed up by solid documentation of approval before construction,” he said.
To bolster design immunity, timing and authorization are everything. “The gold standard of design immunity is approval by a city council or board of directors,” said Dean. “Ideally, the resolution would explicitly state that the approval is for design immunity, that it’s occurring prior to construction, and that the proposed plan meets all requirements.” Then, what is built needs to match the approved design.
Dean advised that agencies carefully review their municipal codes to ensure that discretionary authority is granted to the right people, especially during department restructuring. Proactive discretionary approval and comprehensive documentation are the keys to a strong design immunity defense.
By understanding the ins and outs of warrants, securing proper pre-construction approval upon each round of design edits, and thoroughly documenting the process, agencies can proactively protect themselves from costly litigation. Design immunity lays the groundwork for responsible, safe public infrastructure planning. Learn how you can improve your planning process with your regional risk manager.
< Back to Full Issue Print Article