Beliefs about error rates and human judgment in forensic science

Forensic science techniques are often used in criminal trials to infer the identity of theperpetrator of crime and jurors often find this evidence very persuasive. Unfortunately, two of the leading causes of wrongful convictions are forensic science testing errors and false or misleading forensic testimony (Saks & Koehler, 2005). Therefore, it is important to understand jurors pre- existing beliefs about forensic science, as these beliefs may impact how they evaluate forensic evidence in the courtroom. In this study, we examine people’s perceptions of the likelihood of error and human judgment involved at each stage of the forensic science process (i.e., collection, storage, testing, analysis, reporting, and presenting). In addition, we examine peoples’ perceptions of the accuracy of — and human judgment involved in — 16 different forensic techniques. We find that, in contrast to what would be expected by the CSI effect literature, participants believed that the process of forensic science involved considerable human judgment and was relatively error-prone. In addition, participants had wide-ranging beliefs about the accuracy of various forensic techniques, ranging from 65.18% (document analysis) up to 89.95% (DNA). For some forensic techniques, estimates were lower than that found in experimental proficiency studies, suggesting that our participants are more skeptical of certain forensic evidence than they need to be. Keywords: Forensic science, forensic evidence, accuracy, error rate, CSI effect.

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The CSI Effect

10.31228/osf.io/6dsfb ◽

2017 ◽

Author(s):

Jason Chin

Keyword(s):

Forensic Science ◽

Burden Of Proof ◽

High Standard ◽

Juror Decision Making ◽

Scholarly Work ◽

Television Programs ◽

Forensic Evidence ◽

Csi Effect ◽

Real Phenomenon ◽

Scene Investigation

The CSI Effect posits that exposure to television programs that portray forensic science (e.g., CSI: Crime Scene Investigation) can change the way jurors evaluate forensic evidence. The most commonly researched hypothesis under the CSI Effect suggests that shows like CSI depict an unrealistically high standard of forensic science and thus unreasonably inflate the expectations of jurors. Jurors are thus more likely to vote to acquit, and prosecutors face higher burden of proof. We review (1) the theory behind the CSI Effect, (2) the perception of the effect among legal actors, (3) the academic treatment of the effect, and (4) how courts have dealt with the effect. We demonstrate that while legal actors do see the CSI Effect as a serious issue, there is virtually no empirical evidence suggesting it is a real phenomenon. Moreover, many of the remedies employed by courts may do no more than introduce bias into juror decision making or even trigger the CSI Effect when it would not normally occur (i.e., the self-fulfilling prophesy). We end with suggestions for the proper treatment of the CSI Effect in courts, and directions for future scholarly work.

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Beliefs about error rates and human judgment in forensic science

Forensic Science International ◽

10.1016/j.forsciint.2019.01.034 ◽

2019 ◽

Vol 297 ◽

pp. 138-147 ◽

Cited By ~ 9

Author(s):

Gianni Ribeiro ◽

Jason M. Tangen ◽

Blake M. McKimmie

Keyword(s):

Forensic Science ◽

Error Rates ◽

Human Judgment

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Cabining Judicial Discretion Over Forensic Evidence with a New Special Relevance Rule

Michigan Law Review ◽

10.36644/mlr.117.1.cabining ◽

2018 ◽

pp. 173

Author(s):

Emma Shoucair

Keyword(s):

Best Practices ◽

Forensic Science ◽

Judicial Discretion ◽

Forensic Evidence ◽

Criminal Trials ◽

Science Reform ◽

Rules Of Evidence ◽

Federal Rules Of Evidence ◽

Special Relevance

Modern forensic evidence suffers from a number of flaws, including insufficient scientific grounding, exaggerated testimony, lack of uniform best practices, and an inefficacious standard for admission that regularly allows judges to admit scientifically unsound evidence. This Note discusses these problems, lays out the current landscape of forensic science reform, and suggests the addition of a new special relevance rule to the Federal Rules of Evidence (and similar rules in state evidence codes). This proposed rule would cabin judicial discretion to admit non-DNA forensic evidence by barring prosecutorial introduction of such evidence in criminal trials absent a competing defense expert or a high showing of scientific viability.

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Sem/X-Ray Applications to the Forensic Science Field

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100091937 ◽

1976 ◽

Vol 34 ◽

pp. 390-391

Author(s):

K. Culbreth

Keyword(s):

Forensic Science ◽

Depth Of Field ◽

Surface Phenomena ◽

Criminal Cases ◽

Forensic Evidence ◽

Science Field ◽

X Ray ◽

Hit And Run ◽

Evaluation Of Evidence ◽

Scanning Electron

The introduction of scanning electron microscopy and energy dispersive x-ray analysis to forensic science has provided additional methods by which investigative evidence can be analyzed. The importance of evidence from the scene of a crime or from the personal belongings of a victim and suspect has resulted in the development and evaluation of SEM/x-ray analysis applications to various types of forensic evidence. The intent of this paper is to describe some of these applications and to relate their importance to the investigation of criminal cases.The depth of field and high resolution of the SEM are an asset to the evaluation of evidence with respect to surface phenomena and physical matches (1). Fig. 1 shows a Phillips screw which has been reconstructed after the head and shank were separated during a hit-and-run accident.

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Forensic science evidence: Naive estimates of false positive error rates and reliability

10.31234/osf.io/anxur ◽

2020 ◽

Author(s):

Kristy Martire ◽

Agnes Bali ◽

Kaye Ballantyne ◽

Gary Edmond ◽

Richard Kemp ◽

...

Keyword(s):

Forensic Science ◽

False Positive ◽

Error Rates ◽

Forensic Sciences ◽

Positive Error ◽

False Positive Error ◽

Reliability Estimates ◽

Positive Report ◽

Science Evidence ◽

Science Disciplines

We do not know how often false positive reports are made in a range of forensic science disciplines. In the absence of this information it is important to understand the naive beliefs held by potential jurors about forensic science evidence reliability. It is these beliefs that will shape evaluations at trial. This descriptive study adds to our knowledge about naive beliefs by: 1) measuring jury-eligible (lay) perceptions of reliability for the largest range of forensic science disciplines to date, over three waves of data collection between 2011 and 2016 (n = 674); 2) calibrating reliability ratings with false positive report estimates; and 3) comparing lay reliability estimates with those of an opportunity sample of forensic practitioners (n = 53). Overall the data suggest that both jury-eligible participants and practitioners consider forensic evidence highly reliable. When compared to best or plausible estimates of reliability and error in the forensic sciences these views appear to overestimate reliability and underestimate the frequency of false positive errors. This result highlights the importance of collecting and disseminating empirically derived estimates of false positive error rates to ensure that practitioners and potential jurors have a realistic impression of the value of forensic science evidence.

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