Feigned Adjudicative Incompetence

Abstract

Psychological assessments are highly dependent on the forthrightness and sincere efforts of examinees. In particular, evaluations in forensic settings must consider whether feigning or other response styles are utilized to intentionally distort the clinical presentation. The current study examines the effectiveness of the Inventory of Legal Knowledge (ILK) at detecting feigned incompetency within a sample of jail detainees. As an ancillary goal, several scales of the Standardized Assessment of Miranda Abilities were included in the same within-subjects simulation design. Results of the total ILK score raised concerns regarding the mischaracterization of genuine offenders as "suggestive of feigning." Pending cross-validation, however, a Revised ILK proved highly effective, using a floor effect detection strategy. Although intended for Miranda-specific abilities, several detection strategies on the Standardized Assessment of Miranda Abilities appeared to be very promising within a broadened context of feigned incompetency.

Feigned Miranda Impairment by Legally Involved Juveniles: The Vulnerability of Forensic Measures and the Development of Effective Screens

“…For the genuine condition (i.e., standard instructions), archival data were previously collected as part of programmatic Miranda research supported by the National Science Foundation (NSF) Law and Social Sciences Program. As summarized in the Introduction, the programmatic results have been previously reported (Rogers et al, 2016; Rogers, Robinson, & Henry, 2017; Sharf, Rogers, & Williams, 2017; Sharf, Rogers, Williams, & Drogin, 2017). For the feigning condition (i.e., simulation of impaired Miranda abilities), new data were collected from one of the previously used research sites.…”

“…Rogers and his colleagues (Rogers, Henry, Sharf, Robinson, & Williams, 2017; Rogers, Robinson, & Henry, 2017) conducted two feigning investigations on two SAMA measures using adult detainees. In Rogers, Robinson, and Henry (2017), detainees simulated adjudicative incompetence on two SAMA measures: the MVS and the Miranda Quiz (MQ; Rogers, Sewell, et al, 2012). Predictably, detainees had no difficulty in feigning severe impairment on the MVS and MQ.…”

“…As a result, Rogers, Robinson, and Henry (2017) utilized the “floor effect” (FE) detection strategy, which utilizes items that are “too easy to miss” (Rogers & Gillard, 2011, p. 177). On the MVS–Easy (MVS-E) subscale, 99% of the normative sample scored at 13 or above (Rogers, Sewell, et al, 2012).…”

“…On the MVS–Easy (MVS-E) subscale, 99% of the normative sample scored at 13 or above (Rogers, Sewell, et al, 2012). Therefore, Rogers, Robinson, and Henry (2017) used MVS-E-99 < 13 as the cut score. As expected, it had exceptional specificity (.99), while identifying half (sensitivity = .51) of feigners.…”

Validity and Representative Data of the MRCI With Legally Involved Juveniles

“…SAMA research (Rogers, Robinson, & Henry, 2015) has demonstrated how easily adult detainees can appear to be extremely impaired with respect to their Miranda abilities. Presumably, the MRCI is no exception, especially given the transparency of its items.…”