System dynamics modeling in the legal arena: meeting the challenges of expert witness admissibility

Abstract

System dynamics models have been used in legal disputes since the late 1970s to prove and quantify damages. But such use of these models to support expert witness testimony presents challenges generally not encountered in non-dispute applications of system dynamics. Perhaps the most important such challenge is establishing admissibility of expert testimony supported by system dynamics models under the prevailing standards laid down by the US Supreme Court (Daubert standards) that lean heavily on the scientific method. Best-practice system dynamics work adheres to the scientific method and should prove admissible. Work that does not adhere to the scientific method or uses less stringent standards is vulnerable to being ruled inadmissible in such challenges. In particular, use of system dynamics work as a basis for opposing expert testimony must improve significantly, to meet the current admissibility standards. The stakes are high because current and future cases are likely to set precedents that will significantly affect future use of system dynamics in the legal arena, and because legal admissibility will doubtless impact the broader perception of the legitimacy of system dynamics analysis.

System dynamics applied to project management: a survey, assessment, and directions for future research

“…PRA has done more than 45 such projects (Stephens et al, 2005). All have been settled out of court on favorable terms to the contractor (the usual PRA client), with the typical award averaging 50% more than with traditional dispute resolution approaches, supporting the power of system dynamics to add value to these investigations.…”

Managing Organizational Growth and Dynamic Complexity

“…crime (Homer 1993;Coyle and Alexander 1997;Stephens et al 2005;Jaen and Dyner 2008) or terrorism modeling (Grynkewich and Reifel 2006), have been developed. Also, SD applications to individual public institutions (or parts of them) have been done, such as, for instance, in the cases of hospitals, Universities (Barlas and Diker 2000) and even Courts (Bernstein 1994).…”

Validating Simulation Models: A General Framework and Four Applied Examples

“…and the plaintiff companies, the so-called Daubert discipline: 32 As Stephens et al (2005) recount, the 1993 Daubert decision made an explicit link between the reliability of an expert's testimony and the expert's use of scientific knowledge derived by use of the scientific method. The 1999 Kumho Tire decision extended the Daubert standards to testimony based on "technical" or "other specialised" knowledge.…”

“…In a paper rousing the system dynamics (Forrester 1961) simulation modelling community to meet the current standards for expert witness admissibility, Stephens et al (2005) summarise the Daubert criteria and sub-criteria. Table 1 summarises this. System dynamics simulations are quite different from AB simulations: possessing only a single level-they model the individual, or the firm, or the organisation, or the society-they cannot model interactions between scales or levels, and so do not exhibit emergent behaviour (Gilbert and Troitzsch 2005).…”

“…34 Moreover, a list of 23 peer-reviewed journals in which system dynamics work has been published (Stephens et al 2005, Table 2) reveals that this methodology is much more associated with managerial and engineering issues than with micro-economic and market-related issues: only two of the 23 journals could be regarded as economics journals. Stephens et al 2005) 1.…”