Insights: Mt. Everest— We Are Going to Lose Many

INSIGHTS

Mt. Everest—
We Are Going to Lose Many:

A Survey of Fingerprint Examiners’ Attitudes Towards Probabilistic Reporting

OVERVIEW

Traditionally, forensic examiners tend to use categorical language in their reports, presenting evidence in broad terms such as “identification” or “exclusion.” There have been efforts in recent years to promote the use of more probabilistic language, but many examiners have expressed concerns about the proposed change.

Researchers funded by CSAFE surveyed fingerprint examiners to better understand how examiners feel about probabilistic reporting and to identify obstacles impeding its adoption.

Lead Researchers

H. Swofford
S. Cole 
V. King

Journal

Law, Probability, and Risk

Publication Date

7 April 2021

Goals

1

Learn what kind of language forensic examiners currently use when reporting evidence.

2

Gauge attitudes toward probabilistic reporting and the reasoning behind those attitudes.

3

Explore examiners’ understanding of probabilistic reporting.

The Study

Results

Only 10% of participants reported using probabilistic language
0%
Only 2% actually used probabilistic language for the open-response question.
0%
58% felt that
probabilistic language was
not an appropriate direction
for the field.
0%
  • The most common concern was that “weaker,” more uncertain terms could be misunderstood by jurors or used by defense attorneys to “undersell” the strength of their findings.
  • Another concern was that a viable probabilistic model was not ready for use in a field as subjective as friction ridge analysis –– and may not even be possible.
  • While many felt that probabilistic language may be more accurate –– they preferred categorical terms as “stronger” –– and more in line with over a century of institutional norms.

Focus on the future

 

The views of the participants were not a handful of outdated “myths” that need to be debunked, but a wide and varied array of strongly held beliefs. Many practitioners are concerned about “consumption” issues –– how lawyers, judges, and juries will  understand the evidence –– that are arguably outside their role as forensic scientists.

While many participants expressed interest in probabilistic reporting, they also felt they were not properly trained to understand probabilities since it has never been a formal requirement. Additional education and resources could help examiners more confidently adopt the practice.

Insights: Judges and Forensic Science Education: A national survey

INSIGHTS

Judges & Forensic Science Education:

A national survey

OVERVIEW

Forensic evidence can play a crucial role in adjudicating a criminal trial. As scientific authorities scrutinize the reliability of many forensic methods, it is important for judges to be trained and educated to make more informed decisions. Since most judges lack a scientific background, additional training may play an important role. However, the effectiveness of additional training and how it affects judges’ perception of forensic evidence is unknown.

Lead Researchers

Brandon L. Garrett
Brett O. Gardner
Evan Murphy
Patrick Grimes

Journal

Forensic Science International

Publication Date

April 2021

Goals

In collaboration with the National Judicial College (NJC), researchers conducted a survey of 164 judges from 39 states who had participated in NJC programs in order to:

Learn judges’ backgrounds and training in forensic science.

Discover their views on the reliability of modern forensic disciplines.

Understand what additional materials and training judges need to better evaluate forensic science.

The Study

1

In part one, the judges described their past experience with forensic science and estimated a percentage of past cases that dealt with forensic evidence.

2

In part two, the judges reported the
amount of training they had involving forensic science, described the availability of training materials, and identified the resources they want in the future.

3

In part three, the judges described their familiarity with statistical methods and estimated the error rates in common forensic science disciplines.

Results

37.4% past cases involving forensic evidence
0%
14.7% past cases with hearings on admissibility of evidence
0%
13.5% past cases with forensic evidence ruled inadmissible
0%
  • An overwhelming majority received training on forensic evidence through further education as a judge but suggested more of this training should occur in law school.
  • They believed that DNA evidence was the most reliable form of forensic evidence –– and that bitemarks and shoeprints were the least reliable.
  • Judges who reported more extensive training were more likely to view themselves as gatekeepers of valid forensic science testimony and reported a higher percentage of evidence they ruled inadmissible.
  • On average, judges seem to underestimate the error rate of most forensic methods, though to a much lesser extent than lay people, lawyers, or even some forensic practitioners.
0%

of judges endorsed more than one week of training specific to forensic science evidence.

Focus on the future

 

The surveyed judges typically relied on journal articles, expert testimony, case law, and further education, but noted that these resources were not readily accessible. Additional education would help judges in their role as gatekeeper to prevent “junk science” being presented at trial.

Judges expressed a desire for additional training and online resources, especially in fields they rated as more reliable. Those include digital, DNA, and toxicology evidence –– these resources would allow judges to make more informed rulings on technical subjects.

Insights: Battling to a Draw

INSIGHTS

Battling to a Draw:

Defense Expert Rebuttal Can Neutralize Prosecution Fingerprint Evidence

OVERVIEW

While all forensic science disciplines pose some risk of error, the public typically believes that testimony from fingerprint experts is infallible. By employing rebuttal experts who can educate jurors about the risk of errors or provide opposing evidence, courts can counter this tendency. CSAFE funded researchers conducted a survey to study the effect of rebuttal experts on jurors’ perceptions.

Lead Researchers

Gregory Mitchell
Brandon L. Garrett

Journal

Applied Cognitive Psychology

Publication Date

4 April 2021

Goals

1

Determine if a rebuttal expert’s  testimony can affect jurors’ beliefs in the reliability of fingerprint evidence.

2

Examine the responses of jurors with different levels of concern about false acquittals versus false convictions.

The Study

1000

Participants completed a survey which included questions regarding their concerns about false convictions or false acquittals.

The participants were then assigned to random mock trial conditions:

Control condition with no fingerprint evidence

Fingerprint expert testimony with no rebuttal

A methodological rebuttal: the expert focuses on the subjective nature of fingerprint analysis as a whole

An “inconclusive” rebuttal: the expert opines their own comparison was inconclusive due to the poor quality of the evidence

An “exclusion” rebuttal: the expert states that their own comparison shows the defendant could not have been the source of the fingerprints

Results

Trial Condition

% Voting for Conviction

Trial Error Aversions

Mean Likelihood D Committed Robbery

Focus on the future

 

While exclusion and inconclusive rebuttals provided the best results for the defense, the methodological rebuttal still significantly impacted the jurors’ views on fingerprint evidence.

Traditional cross-examination seems to have mixed results with forensic experts. This implies that a rebuttal testimony can be more effective and reliable, while producing long-term changes in jurors’ attitudes.

While a rebuttal expert’s testimony can be powerful, much of that power depends on the individual jurors’ personal aversions to trial errors. This could be an important consideration for jury selection in the future.

Check out these resources for additional research on forensic evidence and juries: