Special Problems and Populations in Feigned Incompetence

This chapter addresses assessment of feigning or exaggeration in cases involving claimed amnesia for the crime, in intellectually disabled defendants, and in adolescent examinees. Claimed amnesia for the offense is one of the most common forms of feigning in criminal defendants, and multiple tests, including the crime-specific symptom validity test, as well as self-report measures and traditional validity tests, permit assessment of claimed memory problems. Intellectually disabled defendants, whose reading or verbal ability may compromise self-report measures and even structured interviews, present multiple challenges for validity assessment. Further, many performance validity tests are vulnerable to false positives for such examinees and cannot distinguish low ability from poor effort. This chapter suggests ways in which collateral data, such as prior IQ scores, can help inform the competency judgment. Finally, adolescent defendants present difficulty because much less research has been conducted on response style in non-adults. The available data are reviewed and suggestions are offered.

The Evaluation

This chapter considers evaluation strategies beginning from receipt of the referral to the conclusion of the interview. It emphasizes the value of obtaining information before the evaluation, particularly from police reports, input from the defense attorney, and school and/or psychiatric records. Examiners are encouraged to covertly observe the examinee’s speech and demeanor and to seek out sources of collateral information, which may include data from jails and people in the community. The importance of avoiding bias and focusing on relevant information is emphasized. The limitations of collateral sources, such as from treatment providers and disability exams from institutions such as the Veterans Administration and Social Security Administration, are highlighted. The use of Internet data and associated ethical considerations are discussed, and demographic factors and behavioral indicators of feigning or poor effort are presented.

Report Writing and Testimony

This chapter examines the purposes of a forensic report and the choices an author faces regarding a report’s structure, content, and tone. The chapter presents suggestions for steps an examiner can take during the information-gathering stage that will benefit the assessment and make report writing more efficient. Prior recommendations for forensic reports in general are reviewed, including means for proactively addressing possible bias. Suggestions for new formats and innovation are advanced, as is a checklist of desirable CST report attributes. The chapter also presents recommendations for testimony, which, in turn, have implications for report length and format. The research on effective testimony is briefly reviewed, and helpful tips are offered.

Tests of Feigned or Exaggerated Cognitive Impairment

This chapter reviews the most popular and promising instruments for assessing poor effort or feigned cognitive impairment. Referred to as performance validity tests (PVTs), these instruments vary from very brief to quite long and also vary substantially in sophistication and performance. The advantages and disadvantages of each are reported along with the costs of their use (time and money), diagnostic statistics, and recommended cutoff scores. The various PVTs discussed in the chapter are well validated in neurological samples but less so in psychiatric ones. The chapter concludes by noting that although many PVTs are now described as effort tests, there has been no research to accurately measure how much mental effort different tests require.

CST Instruments and General Clinical Measures

This chapter discusses the most commonly used instruments for assessing competency to stand trial, their vulnerability to feigning, and attempts and approaches to remedying this deficiency. In contrast, general clinical measures such as the Minnesota Multiphasic Inventory–2, the Minnesota Multiphasic Inventory–Restructured Form, and the Personality Assessment Inventory are both well-armed and well-researched as self-report validity tests. Each has multiple validity indexes and scales, including those that are not included in the publisher’s scoring services. The rationale and research regarding these indices are reviewed, with emphasis on studies involving criminal defendants, and recommended cutoff cutoff scores, with associated diagnostic statistics, are provided.

Measures of Feigned or Exaggerated Incompetence

This chapter describes and reviews the published instruments available to assess feigned incompetence to stand trial. The Inventory of Legal Knowledge has already gained considerable acceptance despite having some significant limitations. The ECST-R Atypical Presentation Scales are included as part of the ECST-R competency assessment instrument and are billed as screening tests for feigned incompetence. However, they address only feigned psychopathology, not feigned cognitive impairment or ignorance of the court system, and are billed as suitable only for screening, not diagnostic, purposes. The strengths and weaknesses of the ILK and the ECST-R are discussed in detail, as are emerging instruments and detection strategies.

Introduction

This chapter introduces the reader to negative response bias—malingering, feigning, and lack of cooperation, and their prevalence in competency to stand trial evaluations. The chapter cites a number of studies that examined the rate of feigning in competency assessments and identifies factors that are likely to affect the base rate of feigning. Styles of negative response bias are also discussed, as is the possibility that a legitimately mentally ill defendant might deny psychiatric problems. Finally, the chapter summarizes recent legal decisions, from both state and federal jurisdictions, that comment on feigning or malingering in the context of a CST evaluation or hearing.

Systemic, Policy, and Research Issues

This chapter briefly recaps the major findings from the preceding chapters and discusses the enormous implications of the transition from inpatient to outpatient CST assessment over the past 20 years. Along with low fees for outpatient CST examinations, this shift to outpatient assessment has led to a greater urgency for examiners to be able to address negative response bias in a time-efficient manner. The chapter reviews the time requirements for various validity tests and other data that may inform validity assessment; it also considers advantages or disadvantages of the location of evaluations and provides recommendations regarding situations in which a second opinion CST exam is ordered. Recommendations for public policy and future CST research are offered.

A Survey of Competency to Stand Trial Examiners

This chapter reports the results from a nationwide survey of experienced CST examiners regarding their practices, preferences for instruments, and use of collateral data. These examiners also provided estimates of different types of invalid responding (feigned cognitive impairment, amnesia, psychopathology, ignorance of court system, physical infirmity, poor effort) seen in CST defendants. Desirable attributes of CST instruments were assessed, as was the standing of major instruments on each of these attributes. Moderators such as ABPP status, inpatient or outpatient setting, and defense versus prosecution orientation were assessed for their effects on other variables such as instrument choice, use of tests or collateral sources, and estimated rates of invalid responding.

Means of Combining or Summarizing Data

This chapter considers the ways that different facts and test results can be synthesized and summarized. The Slick criteria, which were designed to facilitate reliable encoding of the data that might be used to judge the validity of an examinee’s presentation during a neuropsychological evaluation, are discussed along with suggested modifications, criticisms, and alternatives. The chapter discusses several quantitative approaches that have been proposed to objectively weigh evidence of feigning, including below-chance performance and estimating the probability of multiple validity test failures. The challenges of creating similar criteria for feigned psychopathology and incompetence are presented, and the importance of considering poor effort (as opposed to an exclusive focus on malingering or feigning) is discussed.