He actually didn't. From what I heard on Opening Arguments, he said they could be called looters and rioters in the closing argument if they could be proven as such.
I think there's horrible stuff the judge has done, but victims and looters / rioters aren't part of it. And, they're not going to be why Rittenhouse is going to walk free.
It sounds to be that, more than anything else, this is not a judicial system failure, but a legislative failure. That Rittenhouse went way out of his way looking for trouble, found it, and then killed 3 people, should be very illegal, but it is apparently not. That is a problem with laws about guns, and self defense.