You are absolutely right, because these talwars live ina flat , and if these were present at the scene , than in every case they should have come up for rescue of their daughter.Even on some news channel Nupur talwar said that it is usual that hemraj sometime went in to arushis room and Arushi is getting older like any other teenager. This is definetly rape and murder case. Talwars may be at some party on that night, which thought to be immoral and iilegal in society , so they are just trying to shut-off the case. Because no parents will make statement that Murderers are roaming freely , until unless they know who are they( murderers).
