Standard of Proof in Civil Cases and Degree of Expert Witness Certainty

Excerpted from SEAK’s Course: How to Assist An Expert Witness Practice: The Support Staff Program

The burden of proof in civil cases is preponderance of the evidence, which means, more likely than not. So, if you look at me, these are my hands. These are the scales of justice. If you put one feather on this side, it’s 50.0001%. That’s enough in a civil case. It is a completely different ballgame. It’s a much easier standard of proof because it’s just money they’re fighting about, generally, okay? So you don’t worry about that stuff. This is a relatively low standard, okay.

Now, when experts express opinions, the opinion only needs to be expressed based upon a reasonable degree of certainty, meaning, more likely than not. That’s the expert’s ticket into court, more likely than not. They don’t have to be 100,000% sure. They don’t have to bet their grandkid’s life on it, okay. It’s just a reasonable degree of certainty. That’s how experts testify, okay. So, they don’t have to be 100% sure. But, the burden of proof in a civil case is much, much lower, which is one of the reasons you get results such as OJ Simpson acquitted in the criminal case but found liable for $25 million in the civil case for killing his wife and Mr. Goldman.