If you have watched a courtroom drama, you have probably heard of the prosecution or defense calling an "expert witness". But in a day and age when everyone claims to be an expert in something, how can these specialized witnesses actually be trusted to help jurors understand complicated, technical concepts. What types of expert testimony may be permitted, and who qualifies as an expert?
Who Can Be an Expert Witness?
Rules about expert witnesses are set by state and federal rules of evidence, depending on whether the case is in state or federal court. A qualified expert witness is someone who has knowledge, skill, education, experience, or training in a specialized field. Under federal rules, experts must base their testimony on sufficient facts or data similar to those also relied upon by experts in their field, in order to help the jury understand issues that typically require advanced knowledge. While non-expert witnesses can only testify about what they've seen or heard, expert witnesses are generally allowed to give their specialized or professional opinion.
Admissibility of Scientific Testimony
One issue that often arises with expert witnesses is whether scientific testimony will be allowed in court. For scientific issues that aren't seriously disputed, judges may take judicial notice. This means that the judge can introduce the testimony at fact because it's something a person of average intelligence already knows. For more controversial scientific issues, courts must assess if the testing methods were reliable before admitting the expert's testimony. Courts will look at whether or not the data has been peer reviewed and whether or not there is a high error rate in the testing.
The rules regarding expert witnesses can get complicated, so contact the Kyle Law Firm today so you can learn more about presenting your own expert witness and the restrictions associated with this kind of expert testimony.