Testifying as an Expert Witness: Qualification & Best Practices

Instructor: Rachelle Fobbs

Rachelle has a MS in Forensic Science. She has extensive crime lab experience which includes training and testimony as an expert witness.

In this lesson, the definition of an expert and the process of being qualified as an expert witness in court will be described. Tips on testifying as an expert will also be provided.

Qualifying as an Expert Witness

An expert is someone who has specialized training and education in a topic, which gives them more knowledge than the average person. Before testifying, an expert witness must be qualified by the court. This process is called voir dire and involves the attorneys questioning the witness about his/her qualifications, such as education, training and experience. The witness will also often be asked if he/she has testified in court as an expert before and if they are being paid for their testimony. Both lawyers have an opportunity to question the expert about his qualifications, and once that is complete, the judge will rule that the individual is an expert in a certain topic.

Tips for Expert Testimony

Be Prepared

If possible, have a pre-trial conference with the attorney so you know what to expect during the trial. Go over a list of questions you will be asked during direct examination, the questioning by the attorney who called you as a witness. You may need to educate the attorney on the topic of your testimony; you can even provide him/her with questions that will best allow you to explain important points to the jury. You can also tell the attorney what NOT to ask and how to handle follow-up questions after the other attorney questions you.

Review all your notes and paperwork pertaining to the case you will be testifying about, and know them inside and out. You can refer to your report or notes during your testimony, but it is best to answer without looking at your notes after every question. Just make sure your papers are organized and legible, so you can find the information if you do have to refer to your notes.

Practice Makes Perfect

Whether it's the first or twentieth time you are testifying, you will most likely be nervous. It's a good idea to rehearse your answers to the questions you know you will be asked, such as the voir dire questions and any basic definitions or concepts in your field. Once you've testified a few times, you will have a better idea of what questions are asked most often, and you can practice answering them in an expert manner.

Appearance of an Expert Witness

As an expert witness, the first impression you give the jury is your appearance. Expert witnesses should look professional and well-groomed. Most expert witnesses wear a suit of a neutral color, such as black, gray, or blue. Bright colors and makeup or jewelry can be distracting to the jury and should be avoided, as you want the jury to concentrate on your testimony and not your appearance.



During cross-examination, the attorney representing the other side, the attorney who did not call you as a witness, will question you. For example, if you are called as a witness for the prosecution or plaintiff, the defense attorney will most likely ask you questions in cross-examination. You have no way of anticipating what that attorney will ask you. During cross-examination, lawyers will often ask leading questions, in which the answer is already suggested, thus limiting the way you respond. When this happens, answer the question to the best of your ability. Also, if there is an objection, wait for the judge to rule on it before answering. The judge or attorney will then instruct you to answer, or the attorney may have to ask a different question instead.

You may also be asked questions the attorney wants you to answer with a 'yes' or 'no' response, when the question actually requires more of an explanation. You can explain that you cannot answer with a simple 'yes' or 'no.' You can also ask them to repeat the question or say you don't understand what they're asking, which gives you more time to think about your response. If you don't know the answer to a question, say 'I don't know'. Be honest; remember, you are under oath!

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it now
Create an account to start this course today
Used by over 30 million students worldwide
Create an account