Then he shouldn't be indicted, arrested, or convicted.
* * * *
The standard for an arrest without a warrant requires only probable cause that the suspect committed a crime, and does not require 100% knowledge that the suspect committed the crime.
The standard for an indictment doesn't require determination that the suspect is guilty without a doubt. (First, there's the issue of grand jury indictment v. prosecutor's discretion v. preliminary hearing v. no required unanimous grand jury vote v. standard of grand jury to bring indictment v. standard under which prosecutor should seek indictment v. no adversarial system in grand jury v. kitchen sink. That's first.)
The standard for a criminal conviction requires only guilt 'beyond a reasonable doubt,' and not guilt beyond all doubt
Ergo, neither arrest, indictment, nor conviction, nor the combination of all of the above, requires that we know, or will ever know the absoulute guilt of the suspect/defendant.
I'm willing to arrest, indict, and convict without 100% knowledge. That's part of our judicial system.
And yet, the probable cause that a crime was committed seems to be sadly lacking.
You don’t arrest someone because a bunch of racist idiots threaten to riot
You might be willing to convict on less than 100% certainty, but I am not willing to convict on less than 50% certainty. If law enforcement thought there was a reasonable chance that a jury would convict, Officer Wilson would be in a cell this minute.