A trial court in Mumbai on Saturday accepted that Pravin Mahajan had pre-planned the murder of his elder brother Pramod Mahajan.
Pravin faces charges under section 302 (murder) and 449 (house trespass) for killing Pramod, the late leader of Bharatiya Janata Party (BJP).
In his ongoing dictation of the judgement of the most keenly watched murder trial, sessions court judge SP Davare observed that the prosecution has proved its case "beyond reasonable doubt".
The court also accepted that there were sufficient injuries to Pramod's vital organs leading to his death.
The court said the SMSs allegedly sent by Pravin to Pramod proved that the murder had been pre-planned.
The dictation of the final judgement is expected to conclude on Monday.
Following that, the quantum of sentence will be pronounced after the court hears the arguments between the defence and prosecution lawyers.
Pravin had pumped three bullets into Pramod on the morning of April 22, 2006 at the latter's flat in Worli, central Mumbai. A fourth bullet had got stuck when the revolver malfunctioned.
After the shooting, Pravin walked down to the nearby Worli police station and surrendered.
Following sustained police investigations, which went on for 10 months, Pravin's trial commenced in March this year before the court.
Earlier, the court had rejected the prosecution's theory that money could be the motive and the prime cause behind the acrimony between the two siblings, which led to the sensational killing.
After a brief open court recording of Pravin's statement last month, the remaining testimony was recorded in camera since certain private details pertaining to Pramod's life came to the fore.
During the trial, the witnesses who deposed included Rekha, Pramod's wife, daughter Poonam, brother-in-law Gopinath Munde and Pravin's wife Sarangi.
Pramod's utterances to Munde who rushed him to the hospital have been treated as a dying declaration by the court, which proved to be a clinching point in the trial.