Medical experts have been used in state and federal courts for decades. Their primary role is to explain to a jury or other justice panel exactly what they believe medically speaking, with regard to a party involved in the legal proceeding. Many of these experts take the stand under oath and use illustrations to show their medical opinion. These illustrations or props might include x-rays, medical diagrams or other pictures to help show their stance.
The primary role of the medical expert is to offer up their opinion to the jury in a fair and balanced manner. In hotly contested legal proceedings, both sides have bias and both want to win. The goal of the medical expert is to showcase his or her knowledge in an impartial way. However, this is difficult in some cases, especially since each side often hires its own medical expert, and the medical expert is collecting his paycheck from the attorney, who has a clear and strong bias.
Medical experts are known to charge hefty rates for their services. In most trials, they are on the stand for only a few hours, but many charge as much as $3,000 an hour for their services, meaning the bill can add up very quick. And that hourly rate is often charged even while the medical expert is waiting to testify. Because of the lucrative nature of the position, many medical experts leave their day jobs to enter this industry, simply because of great amount of money involved.
The size of the trial often does not make much of a difference when it comes to demand for medical experts. Even smaller trials might use them, especially if there is some sort of injury alleged to be committed by a suspect. In that case, District attorney's offices often use the medical expert witness service to document the evidence. This gives the jury an expert vision on the injury, one that is not biased by the attorney's presentation. Medical experts used by district attorney's offices are often already county employees. Most are forensic experts who already collect a paycheck from the local government for which they are employed. These kinds of experts don't have the luxury of charging the steep rates that those in the private industry charge.
Despite the high dollar rates, bias in a medical expert can come from either side. Even the government-employed experts can have bias, perhaps based on their close relationships with law enforcement and the prosecuting attorney. Bias is even more existent from the other side, most commonly the defense side, because of the money involved. There are some cases where the expert puts his reputation on the line and the jury does not agree with their position.
Some high profile cases in California, such as the People versus OJ Simpson and the People versus Phil Spector, use medical experts by the dozens. In the case of Spector, the issue was self-defense and how he used the murder weapon.