This is a court, not a logic test. You cannot prove ABSOLUTELY that she was sane enough to be held responsible, but the standard isn’t absolute proof. It is “Would a reasonable person have no REASONABLE DOUBT about her sanity?”
Which the state did prove, except they had 11 unreasonable jurors who decided, probably before the trial began, that “all women must be believed”. They had a judge and a prosecution that bent over backwards to allow the defense to muddy the waters. But I don’t think the trial itself had any impact on the verdict.
You had 11 jurors searching the Internet, reading about her supporters outside, who decided to stand in solidarity against “THE MAN” by insisting, no matter how evil the act, that all women must be believed!
Good comment.