Evidence
“It’s not that I think a fact-finding
committee is necessarily a bad idea.
I’m really just not that interested in
facts.” – WSJ Cartoon
7/1/2016
Phillip G. Clampitt, Ph.D.
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1. Types of evidence
Specific instances
Statistics
Testimony
Illustrations
Imaginary dialogue
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Comparison and
contrast
Definitions
Repetition and
restatement
Cartoons
Phillip G. Clampitt, Ph.D.
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2. Evaluating Evidence
Evaluating Specific
Evidence
 Are the instances
representative?
 Are there enough
instances?
Evaluating Stats
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Have the stats been
collected accurately?
Does the sample conform to
social-scientific principles?
Have terms been clearly
defined?
Are you comparing apples
to apples?
Are the data statistically
significant?
Is the visual presentation of
the data accurate?
Phillip G. Clampitt, Ph.D.
3
Evaluating evidence (cont’d)
Evaluating Lay Testimony
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Did the person have an opportunity to
observe closely and carefully?
Was the person physically capable of
making the observation?
Did the conditions impede accurate
observation?
Does the observer bring preconceived
expectations?
Is the person biased?
Is the person of good moral character?
Are there any other factors that might
adversely influence the observer?
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Evaluating Expert
Testimony
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Does the person have the
necessary formal training?
Is the person an expert in the
subject under investigation?
Is reference to the expert
vague?
Is the expert highly regarded in
the field?
Is the testimony relevant to the
situation?
Was the expert aware of the
significance of the remarks?
Phillip G. Clampitt, Ph.D.
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3. General Principles of Strong
Evidence
Recency
Clarity
Accuracy
Sufficiency
Representativeness
Relevancy
Internal Consistency
External Consistency
Cumulativeness
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Phillip G. Clampitt, Ph.D.
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