Well, Matt IS a really good lawyer - but they really should have spent a LITTLE more time on a court scene, if only to have posed some critical questions.
"So, the suggestion is that this 17-year-old boy - a personal friend and confidant of Tony Stark, to whom he bequeathed the most powerful weapon of mass destruction ever created - is in fact a criminal mastermind? A criminal mastermind who spends his days swinging through the city, saving people from muggings and potentially deadly accidents? Who risked his life several times during the Thanos war, and was in fact among the Disappeared? Whereas Mysterio was a super-hero - although he has now been positively identified as Quentin Beck, a former Stark Industries employee with an expertise in hologram technology and, if this employee record I hold is correct, a history of mental issues? His own associates describe him as a violent and domineering personality, displaying qualities of a paranoid psychopath, not to mention a habitual liar. Your honor, I move to throw this case out, because frankly, it's an embarrassment."
Anyway, they probably did arrest some members of his gang, but it would have been nice to have SOMEONE squeal.