Here is a quote from The Brass Verdict (a Lincoln Lawyer novel) by Michael Connolly:
“Everybody lies. Cops lie. Lawyers lie. Witnesses lie. The victims lie. A trial is a contest of lies. And everybody in the courtroom knows this. The judge knows this. Even the jury knows this. They come into the building knowing they will be lied to. They take their seats in the box and agree to be lied to.”
It’s a fictional work of course.