The standard of care of structural engineers

Structural engineers' “standard of care,” described here as the boundary between negligence and non-negligence, is determined by a judge or jury when a defendant structural engineer is tried for professional negligence. Expert witnesses, testifying for the purpose of aiding the trier of fact, give evidence concerning where that boundary is located and where the defendant's acts or omissions fall relative to that boundary. Recent case law allows judges to exclude expert testimony as inadmissible if it is not developed through valid or reliable means. A major goal of this dissertation is the creation of a valid and reliable method for expert witnesses to arrive at their opinions concerning the standard of care and the defendant engineer's conformance to that level of care. Professional negligence is defined in this dissertation by reference to an approved jury instruction. The ethic of care is described and evaluated as an appropriate structure for examining care in engineering. Several engineering failures are presented to illustrate the concept of the engineer's standard of care, and to examine how the elements of care relate to the engineer's performance in those instances. The understanding of the concept of the standard of care among a small group of practicing structural engineers is measured, and the measuring instrument is proposed for application to the larger population of engineers. A review of the historical record is described, showing the variability of the standard of care of engineers who were practicing at the time of the 1906 San Francisco earthquake. The method developed here uses interpretive case-based reasoning, informed by the Delphi process of expert opinion consensus. Case-based reasoning and Delphi are described, the proposed method is tested, and its validity and reliability are discussed.