Instructions to the Jury on Expert Testimony

Guilt Phase

October 18, 2004

JUDGE: Before you call Mr. Gebler, I want to instruct the jury about expert testimony to sort this out. Ladies and gentlemen of the jury, I'm going to instruct you. You are going to hear this instruction again before the case is submitted to you. But we have had the testimony of all these different experts. Now I'm going to give you a jury instruction to help you assess the testimony of these experts so you have some direction when you are trying to decide what weight you are going to give the testimony of each expert that may be called to testify. This is the instruction. What it says, it says witnesses who have special knowledge, skill, experience, training or education in a particular subject have testified or will testify to certain opinions. This type of witness is referred to as an expert witness. In determining what weight to give to any opinion expressed by an expert witness, you should consider the qualifications and believability of the witness, the facts or material upon which each opinion is based, and the reasons for each opinion. An opinion is only as good as the facts or reasons on which it is based. If you find that any fact has not been proved, or has been disproved, you must consider that in determining the value of the opinion. Likewise, you must consider the strengths and weaknesses of the reasons on which it is based. You are not bound by an opinion. Give each opinion the weight you find it deserves. You may disregard any opinion if you find it to be unreasonable. Now, this instruction applies both to the prosecution experts and to the defense experts that you will be hearing from.