It wasn't a real trial. Just opening and closing arguments, and then a decision. If you want to call that a trial, so be it. It wasn't anything close to a trial the Judiciary would have held.
But then the House didn't exactly have a fair evidentiary hearing. No justice in either case. I thought it was outrageous when the House counsel questioned the Executive's counsel.
Maybe a better description would be the case was summarily dismissed. Rather than any real judgment found. What did they judge? Just the evidence without new, or direct, corroboration.
When you can make the rules to suit your needs, that's what happens. I posted long ago that nobody should be up in arms over what was going to happen.