Bear in mind that District Court Cases are summary hearings in which both parties agree to proceed, quite often because the facts are generally known. If your daughter does have a TV and doesnt have a license, you shouldnt pretend otherwise or try to act the smart alec by saying "where's the proof" etc.
If you do decide to go down the "where's the proof" route, its likely that the TV License people will appeal to the Circuit Criminal Court and have the case dealt with as a full blown criminal case in a more formal court setting with Barristers, jury etc & where witnesses are summonses etc etc. rather than a short and painless District Court hearing. The TV license people would then summons e.g. NTL technican who fitted cable or whoever else physically saw a TV in your daughters possession.
If you daughter is innocent (i.e. didnt have a TV without a license) then by all means fight the charge. But if she's guilty, she'll more likely get a stiffer sentance if shes uncooperative. The best outcome for you in this case is the District Court slap across the wrist, no criminal record and contibution to poor box. If it goes to Circuit Court, she will have a criminal record that she will have to declare if she loses.