The scarcity principle is a phenomenon of human psychology. It may even be an evolutionary trait. It states that we give more value to things we consider rare and less value to things we consider plentiful. It is the reason why we all fight for the last water bottle in an emergency situation or why the last cookie in the pack always seems to taste the best. It is the reason why most infomercials urge you to call within the next 30 minutes or else the offer will expire. It is also the reason why you may want to consider not asking for curative instructions as a trial lawyer unless absolutely necessary.
One study in particular evaluated this principle in car accident trials with mock juries. During these trials three scenarios were tested. In one scenario the jurors did not learn that the defendant had liability insurance. In the other scenario the evidence of liability insurance was admitted without objection. In the third scenario the liability insurance came into the trial, was objected to, and was ruled inadmissible by the judge who gave the jury a curative instruction to that effect. The result of this study highlights the danger of curative instructions.
The first group awarded $33,000 to the Plaintiff. In the second scenario, where the jurors heard there was liability insurance, the jurors awarded an average of $37,000 or $4,000 more than the jurors without the insurance evidence. In the third scenario, however, the jurors awarded an average of $46,000, or $9,000 more than the jurors who were allowed to consider the liability insurance evidence. In essence, the jurors who were given the curative instruction to not consider the liability insurance returned an average of almost 2.5 times the damages of those who were not given the curative instruction.