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Law 101: Legal Guide for the Forensic Expert

Ability to Persuade

Experts may recall the last time something changed their minds on a particular subject. What caused this change? Was it a book, something said at a lecture, information from a television program, or an exchange of ideas with persons who had more information?

People change their opinions for various reasons. One of the expert's objectives as a witness may be to cause the fact-finder to change an opinion about a scientific, technical or factual proposition. The expert's task frequently is to: 

  • Persuade without becoming an advocate.
  • Convince without argument.
  • Encourage a conclusion based upon data presented in an interesting way.

Effective persuasion is subtle. A person is most strongly convinced if he can mentally develop the conclusion for himself rather than having it "spoon-fed" to him by a persuader.

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