Which would make sense, no? They're playing the odds. It's exceedingly rare for any upper-middle class woman to commit a crime. So to be surprised by that is understandable. Take color and class out of it, you need only compare "man accused of crime" vs "woman accused of crime". More will give the woman benefit of the doubt, and they're more likely to be correct than giving the man the benefit of the doubt.
But to be clear, of course anyone accused of a crime should go through the exact same legal process as anyone else. Justice should be blind and operate on the facts of the case. You can't just make assumptions or play the odds in court, obviously.