Krishna's confession statement according to CBI is noteworthy in certain aspects. That Krishna was called by Hemaraj to bring Khukri a day before the murder took place. That he (krishna)was present at the time of the murder and also met Hemaraj just before the night(of murders) That Dr.Hemaraj was innocent. That the girl Aurishi's character was good. These are confessions of Krishna and except the latest confessions all other confessions about Dr.Talwar were all made almost immediately after his arrest. It is now clear that he knows about murders and Hemaraj may also know the murders or it may be that both of them committed the murders but for some reasons , the third person involved might have killed Hemaraj as well after the murder of Aurishi.
It is also clear that this compunder is a tough nut to crack. A hard one. Now he may start singing by providing the vital clues and the weapon to corroborate whatever he confessed. Otherwise a simple confession without corroborating evidence is not admissible in a court of law as an evidence. The law of evidence needs minimum two witnesses and some corroborating evidence for confessions before police officers. Sooner than later ,may be in a week's time the entire episode of this tragic murders would come to light. My feeling is that Dr.Talwar is totally innocent.