It’s legal speak. Before judge or jury or whatever they have concludes anything it’s not certain and thus they need to be a bit careful on how they publicly speak about the matter. Just like a murderer is a ‘suspect’ even if they admitted everything with a smoking gun in their hand. Only after conviction they are by definiton a ‘murderer’.

But I’m glad to see international powers in this circus as USA doesn’t seem to have a working legal system anymore. It might be awfully slow for anything to happen, but at least gears are turning.