In your opinion, which is just as valuable as mine, or not, he committed a crime. You have no evidence that he did commit a crime, but you believe he did and therefore should be punished.
My view is similar to yours, except that if you allege that he committed this alleged crime, you need cast iron proof and evidence that he actually DID commit a crime. Evidence that you don't appear to have.
I could allege that you for example broke the law on les majeste and that you should be punished. The problem I would have, is that I have no evidence, and quite rightly, the charge would be thrown out, simply because of the lack of evidence that would stand up in court.
What you believe, and what I believe, are meaningless unless it can be verified and backed up.
If you wish for another example, Thaksin was legally the PM of Thailand from 2000 to 2006. He won the election in 2000 and won the 2004 election with an overall majority and did so openly and legally. That is a fact.
He was illegally removed from power by a military coup. Another fact. Were the coup leaders ever punished for that. No. Another fact.
Going into a grey area, if there had NOT been a military coup, would Thaksin have been charged or not?
BTW if you claim that he did, it is up to you to prove it, and not me to disprove it.