Isn’t part of the point of an evidentiary hearing to allow prejudicial evidence to be excluded? A completely unreliable eyewitness seems more prejudicial than informative…
Its because nothing in the constitution explicitly forbids the use of unreliable evidence and all of the Supreme Court opinions that dictate when and how evidence is suppressed have to tie back to the constitution somehow. You could argue that using unreliable evidence at trial would be a denial of due process and thus violate the 14th amendment. However, the court has never been receptive to that reasoning as far as I know.
Under the Federal Rules of Evidence, Rule 403, which have been adopted by every state but California, “[t]he court may exclude relevant evidence if its probative value is substantially outweighed by a danger of…unfair prejudice….” So the prejudicial effect has to substantially outweigh the probative value, and the prejudice has to be unfair, and even then, the court may exclude it. The California Evidence Code, section 352, is even clearer: “[t]he court in its discretion may exclude evidence if its probative value is substantially outweighed by the probability that its admission will…create substantial danger of undue prejudice….” So in California, the probative value must be substantially outweighed by the substantial danger of prejudicial effect, the prejudice must be undue, and even then, the court has the discretion to exclude it. The general rule is to admit relevant, material evidence. The prejudicial effect has to be powerful before the evidence will be excluded.
Important to note that the rule says “unfair” prejudice. Any evidence of guilt is prejudicial to the defendant. “Unfair” means what it sounds like: showing it to the jury would deny the defendant a fair trial.
“Unfair” prejudice is where there’s a danger that the jury’s mind is going to be made up based on something illogical. Like something that’s going to get their emotions so riled up that they turn off the thinking part of their brain and just want to convict whoever happens to be in front of them. Gruesome photographs, for example.
Also important to note that the danger of unfair prejudice must “substantially” outweigh its probative value. The case doesn’t really need this piece of evidence, but it’ll have a huge effect on the jury if it comes in.
Also important to note that the decision is entirely up to the judge’s discretion. He “may” keep it out.
Finally, this is a rule of evidence, not an exclusionary rule. It’s a decision made at trial (or in a motion in limine), not at a suppression hearing. It’s not Criminal Procedure, but Evidence law, and we’ll cover it when we get to that subject
I love the Court Clerk’s long answer!
Hahaha – I didn’t even notice it until you pointed that out. I just (incorrectly) assumed that the long “NOOOOOOO” was some artistic pattern at the bottom of the panel.