Why Are Expert Witnesses Used in a Criminal Trial?
When a criminal case is decided by a jury, the State of Nebraska, through the prosecuting attorney, must convince the members of the jury beyond a reasonable doubt that the defendant is guilty of each and every element of the offense with which the defendant is charged. This is not intended to be an easy burden to overcome. On the contrary, the American criminal judicial system is designed to place the burden on the State so innocent people are not wrongfully imprisoned. In order to meet its burden, the State often uses expert witnesses in an attempt to sway the jury and/or to explain concepts that cannot be explained by a layperson.
An expert witness can be used for a seemingly endless number of reasons, but some of the most common uses of experts in criminal trials include:
- Ballistics – if a firearm was used during the commission of the crime, a ballistics expert may be called by the State to testify to the type of firearm used. If a firearm was also recovered from the defendant or the defendant’s property, a ballistics expert may also testify as to whether the bullets from that firearm match the ones recovered at the scene of the crime.
- Bodily fluids – when bodily fluids are involved, including blood, saliva, and semen, an expert may be used to testify to the results of tests run on those fluids. An expert may also testify as to whether there is a match with the corresponding bodily fluids obtained from the defendant. If there is a match, the State will argue the match places the defendant at the scene of the crime.
- Fingerprints – everyone has seen the “dusting for fingerprints” in a movie or television series. Fingerprints are unique, meaning no one has your exact fingerprint. Therefore, if your fingerprints were found at the scene of the crime, it presumptively places you at the scene.
- Cause of death – if the case involves a death, the medical examiner will likely be called to testify as to the cause of that death.
- Insanity defense – insanity is a defense to any crime. But it isn’t as simple as claiming you didn’t know what you were doing at the time. For insanity to be a valid defense, the court must be convinced you meet the legal definition of insanity; this requires an examination by an expert who will offer his/her opinion.
While these are some common uses for an expert witness, just about any type of expert could be used in a criminal trial. Basically, if either side wants to convince the jury of something, and an expert might help, you can count on seeing one at the trial.
Can My Criminal Attorney Use Similar Experts?
Absolutely! For every expert called by the State to testify against you at trial, your criminal defense attorney has a right to hire another expert to testify that the State’s expert is wrong. Sometimes it becomes a “battle of the experts,” with the most convincing expert swaying the jury to his/her point of view on the matter.
Contact Us
If you have been charged with a crime in the State of Nebraska, it is certainly in your best interest to consult with an experienced criminal defense attorney right away. In Nebraska contact Petersen Criminal Defense Law 24 hours a day at 402-509-8070 to discuss your case.
- How to Register a Firearm in Nebraska - Monday, March 13, 2023
- Nebraska Trespassing Laws - Sunday, March 12, 2023
- Murder vs. Manslaughter Charges in Nebraska - Thursday, March 9, 2023