and by "serious" they have to have first hand knowledge of the case.
Those with first hand knowledge of the case are participants (witnesses, prosecutors, grand jury members, etc.) and the overwhelming majority of those with first hand knowledge are not speaking. Those who are not participants, but observe what the participants are doing, are observers. There are serious observers and partisan observers. Even many partisan observers (including Democratic Senators) have backed off the crime meme.
The Journalists who have read and witnessed some of the court proceedings, are very convinced of the seriousness of the crimes..in fact so are the judges.