In the states cases it’s just “beyond reasonable doubt” that is required. I.e. would a reasonable person (one with a brain and no particular axe to grind), believe that there is an equal to or greater than 50% possibility that he did commit the crime. If they do then it meets the burden of “beyond reasonable doubt”.
It doesn’t violate his rights because he hasn’t actually been accused of the crime, it is just the courts stating that they think it’s more likely than not that he did commit the crime.
He will probably double down and demand a criminal case, but that doesn’t matter because there’s already one in progress anyway. It also won’t get his name put back on the ballot.