More than thirty years ago a friend of mine iintroduced me to the book Influence by Robert B. Cialdini Ph.D. (1984). This book has become a classic for those in the field of sales and anyone else dealing with people generally. I have recommended it as required reading for trial lawyers for years. This is not a complex book. There are only six basic principles which Cialdini lists as basic social and psychological principles that form the foundation for persuasion.
The most basic and probably the most important rule is that reciprocity. Cialdini says that this is an extremely powerful rule. Essentially the principle is that when someone does something for you, you feel obligated to do something for them. The other day I received an envelope in the mail which had a dollar bill in it. Of course it was a solicitation to do something. But the principle was that of reciprocity.. I was supposed to feel obligated as result of the gift. When a charity sends you return address labels or you have received some similar "gift" from somene who wants something from you, the rule of reciprocity is being applied. The rule applies even to uninvited gifts It is powerful. It creates an uncomfortable feeling of indebtedness. Even a small favor can produce a willingness to return a much larger favor.What has that to do with trial? Well, the reason lawyers are taught at the Spence Trial College that they should first share something about themselves with the jury before asking the jury to share something with them is because of the rule of reciprocity.
Another principle is that of consistency andt is directly tied to the principle of commitment. People have a need to be and look consistent in their words attitudes and actions. That means that when they make a commitment, especially in public,, they feel obligated to stay with it. S, in voir dire one can apply this rule in a number of ways. If, for example, you are emphasizing the importance of something a commitment out loud by nature will motivate the juror to remain firm to the commitment. In creating a foundation for an excuse for costs, getting the juror to firmly commit to a position which is grounds for a challenge means that even when questioned by the judge the juror is more likely retain the commit position.
A third principle is that of liking. People are far more likely to say yes to an individual they know and like. Liking someone involves a number of factors. One of these is that of common interests and beliefs. Another is physical attractiveness. For trial lawyers, a juror who believes the lawyer is likable, is more likely to agree with them. To the extent you can demonstrate these factors the more likely it is the jurors will follow your advice.
Another principle is that of authority. People tend to feel any pressure for compliance when requested by an authority figure. People who appear to possess levels of knowledge, wisdom, or power often are seen as authority figures. This of course has significant importance when it comes to expert witnesses and other authority figures like law enforcement officers, physicians etc. Think about this principle and the jury instructions. The judge honestly represents someone in a position of authority. Using the judge’s instructions therefor is a good idea for trial lawyers.
Another principle is that of scarcity. People assign more value to something which is what will be scarce. That’s why sales people and advertisements talk about a "limited number." People respond to the loss of freedom by wanting to have more freedom. That includes the ability to have goods or services. Your case should be presented as a unique opportunity for the jury to do something which will not only benefit themselves what the community. It should be seen as a rare chance to become involved in a direct way in improving something that will benefit them. That’s the principle of scarcity.
For a good summary of the book see http://www.rickross.com/reference/brainwashing/brainwashing20.html . I suggest everyone involved in persuasion you read and study the principles in this book.