She's a Core Participant so is entitled to sit up front right in the midst of the action. Unsurprisingly, she is highly motivated to attend and see as much of it as she can. And then, as you say, she is right there in the witnesses' faces and this is often used for effect. There'll be a wtiness who played a part in her victimisation and one of the barristers will say "Jo Hamilton, who sits next to me/who sits here today [suffered as a result of your actions]. What did you do to help/do you say to Jo Hamilton?"
This was actually done yesterday by counsel to the Inquiry cross-examining George Thomson:
Can I pause you there. You said every case that was taken up with you, you took to the Post Office. Let’s scroll back on this page, let’s start at page 2. Jo Hamilton, who sits here today. Did you fight her case with the Post Office?