MO HB1280

Establishes a peer review process for design professionals (architects, landscape architects, land surveyors, and engineers) to evaluate quality and prepare internal lessons learned after substantial completion of projects.

Grants civil liability immunity to outside peer reviewers (third-party design professionals not employed by the firm whose work is being reviewed) who act in good faith and without malice.

Protects "lessons learned" documents (internal meetings, presentations, and communications among employees and partners) from discovery and admissibility in legal proceedings, but allows discovery of other peer review materials.

Prohibits immunity for in-house peer reviews conducted by employees, coworkers, or partners of the design professional whose work is reviewed; such documents remain discoverable and admissible in court.

Sunset provision expires January 1, 2023, unless reauthorized by the general assembly, though the protections continue to apply to peer reviews conducted before the expiration date.