Part of the reason you call a lawyer early is so they can help steer things away from the point where you need a lawyer to mount a criminal defense. Cheaper that way, too.
No crime being committed isn't really the standard. "Due process" is the standard. If you go through the process and the judge decides you're guilty, you're guilty. And you're going to do your time. It doesn't matter whether or not you committed the crime, only that you can prove you were not provided "due process."
Innocent people frequently wind up in prison and even after exculpatory evidence is discovered, it takes A LOT of effort to get them released. Because the state argues "they were provided with due process."
Which is still not really like this case. Hence the author ultimately managing to get out of it without the services of an attorney and without any actual trial taking place.
Yes. You're talking about a specific, I'm talking about a general case. We know that this wasn't the case here because the story didn't end with "I was carted away to prison." My comment was in reference to the general case of US jurisprudence the OP discusses when she says "not only is justice blindfolded, but is blind." In the GENERAL case, you can still be convicted even if exculpatory evidence exists. And this is the point I should have emphasized:
Do not assume that the mere existence of exculpatory evidence will allow you to evade successful prosecution.
(But thankfully, it worked fine in this case and works in many other cases.)