Your mixing civil with criminal matters. I agree that many frivolous criminal claims are filed by the DA, but the only evidence needed to get to a jury is a affidavit of a officer. And they never lie. . . . The proof is in the huge number of the convicted being released because DNA evidence clears them.

As for civil, a frivolous lawsuit may be filed but will never get to a jury if truly frivolous. There are several procedures before a trial date is even set to ensure this.

That said, it is often less expensive to settle a case, civil or criminal, than going to trial. This is why about 95% of all cases resolve through a settlement or plea bargain.