Second answer since I missed your initial point...
If I am actually innocent, there are most likely three scenarios:
1. The DA drops the charges. This is a very common outcome when the case is not a slam dunk.
2. I was a witness to the crime and/or I was in the vicinity of the crime, and for some reason I was not willing to mention this to the DA. This happens a fair bit (esp. the vicinity one), but this is not a "slam dunk guilty" case, and every lawyer will tell you this. My guess is that I would talk to the DA via my lawyer, because I aggressively avoid hanging around places that are likely to have crime (even the white collar variety), and I have nothing to hide.
3. I was framed. This is tricky. My reaction would depend on the context, but again, I keep a healthy distance from people who regularly and knowingly commit crimes.
It seems like a lot of people think that DAs just sit around looking for fake charges to drop on innocent people. This simply does not happen as much as some commenters seem to think it does. Does it happen? Sure. Is this something I ever worry about? No, never.
Do you know of any/many completely innocent people who were wrongly jailed?
The worst I know of is a guy who was trafficking 9,000 pounds of marijuana and got fingered for the whole thing rather than charged as one of three. His issue? He didn't sing and the others did. He got what many would call an unreasonably long sentence given the circumstances (iirc, he did 2 years). Note that a crime had actually been committed (and he admitted to it, at least to friends), so it's not like he was innocent.