You would think an experienced judge is immune to trivial and random psychological tricks… They’re not.
In this study, Birte Englich, Thomas Mussweiler and Fritz Strack, conducted a series of psychological experiments on experienced German judges. The purpose was to test the strength of the ‘anchoring effect’. That is, the subconscious tendency to rely on the first piece of information as a reference point.
This can be a problem because the first piece of information may be irrelevant, meaning the individual is not reasoning objectively; their judgment is distorted.
It turns out, judges are influenced by this effect. So much so, they’ll hand out higher sentences.
In the first study, the judges were exposed to numbers by a journalist. The journalist questioned the judge by asking if the sentence would be higher or lower than a certain number.
The result: the judges that were exposed to the high anchor gave a sentencing of 33 months. The judges that were to exposed the low anchor gave a sentencing of 25 months.
In the second study, the judges were ‘asked to consider the sentencing demands of the prosecutor and the defense attorney before reporting their final decision.’  But, here’s the catch, the judges were informed that the numbers were entirely random.
The result: the judges that were exposed to the high demands gave a sentencing of 6 months. The judges that were exposed to the low demands gave a sentencing of 4 months. Remember, the judges knew that the demands were random.
In the third study, the judges were again ‘asked to consider the sentencing demands of the prosecutor and the defense attorney before reporting their final decision.’  This time, the attorney’s numbers was determined by rolling some dice. To make it worse, the judges threw the dice themselves.
The result: The judges dice that landed on high numbers gave sentencing of 8 months. The judges with low numbers gave a sentencing of 5 months.
So what is going on here?
The anchoring effect.
This psychological phenomenon ‘occurs when people consider a particular value for an unknown quantity before estimating that quantity.’ ‘The estimates stay close to the number that people considered—hence the image of an anchor.’ 
The takeaway message
The dice, the journalist’s demands and the attorneys demands, are not important.
What’s important is that a judge’s decision can be subjected to the anchoring effect.
Why does this matter?
Even though judges typically do not throw dice before making sentencing decisions, they are still constantly exposed to potential sentences and anchors during sentencing decisions. The mass media, visitors to the court hearings, the private opinion of the judge’s partner, family, or neighbors are all possible sources of sentencing demands that should not influence a given sentencing decision.
Sentencing decisions may also be influenced by irrelevant anchors that simply happen to be uppermost in a judge’s mind when making a sentencing decision.
[Our research] suggests that irrelevant influences on sentencing decisions may be a widespread phenomenon. 
So, how can we use the anchoring effect to our advantage? Or more frighteningly, how can we defend ourselves if the opposition uses it?
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