"The jury was sworn in, and the judge ordered Illinois to make its case. The prosecutor refused to do so."
He got off because the prosecutor didn't understand the dilemma at this point, or didn't care. Once a jury is sworn in, if there is a not guilty verdict, even if it is directed by a judge, the case is over and can not be refiled.
A not-guilty verdict in a judge trial can usually be appealed in most states, especially if there was a misapplication of the law by the judge. The judge must enter findings of fact and conclusions of law. A jury has no duty to explain its verdict.
Most of our prosecutors are affirmative action hires. They’re rarely there by merit.