Cognitive bias

cognitive bias

a kind of heuristic i.e. a short-cut way of thinking which minimises cognitive effort and energy and maximises quick, easy solutions to problems and to decision-making.

Anchoring bias

people's tendency to rely too heavily on the first piece of information they receive on a topic

Englich and Mussweiler

Aim

Experiment 1:
to investigate if anchoring bias (that sentencing demands can serve as anchors) could play a significant role in determining sentencing in courtrooms

Experiment 2:
to examine the role of experience in decision making in trial judges

Participants

Experiment 1:
44 German law students in their senior year (32 male, 12 female; mean age of 27.56 years)

Experiment 2: 16 trial judges (12 male, 4 female) recruited from one regional superior court in Germany (mean age of 44.6; mean experience in years = 15.40)

Procedure

Experiment 1:
participants were given a scenario of a rape case and copies of the relevant passages from the penal code.
after the participants had formed an opinion about the case, they were handed the critical questionnaire. about half the participants were told that the prosecutor demanded a sentence of 34 months for the defendant, whereas the other half were told that he demanded a sentence of 12 months*.
they were instructed to indicate whether the given sentence was too low, adequate, or too high.
participants were then asked to indicate the sentence they would give if they were the judge in the case.

Experiment 2:
participants were invited to participate in a study on juridical decision making. they were randomly assigned to one of two experimental conditions.
the same case materials were used as in experiment 1.
the central questionnaire was identical to that of the first experiment. (34 months vs. 12 months).
participants were sent the case materials, the central questionnaire, and general instructions. they were told to form an opinion about the case before answering the questionnaire.

Results

Experiment 1:
when told that the prosecutor recommended a sentence of 34 months, participants recommended on average 8 months longer in prison (M=24.41 months) than when told that the sentence should be 12 months (M=17.64) for the same crime.

Experiment 2:
as in the first experiment, the given sentences were higher when participants evaluated the high demand (M=35.75) than when they evaluated the low demand (M=28.00)
the experienced judges gave higher sentences in both demand conditions

the amount of anchoring did not differ for the two groups

Conclusion

experience does not impact the influence of anchoring bias in the courtroom; thus, judgmental anchoring bias has a strong effect on criminal sentencing decisions

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