He has also been pronounced guilty of molestation and trespassing by the Mumbai court.
The court will pronounce the sentence on July 9. "We want death penalty. It was a gruesome murder. We were living in a hell," said Pallavi's father.
On August 9, 2012, Pallavi was murdered in her rented flat in Wadala.
A security guard of the building Sajjad Ahmed Mughal alias Sajjad Pathan was held for the murder.
Watchman Sajjad Ahmed Mughal entered Pallavi Purkayastha's flat on August 9 with stolen keys and rape on his mind.
He tried to force himself on the lawyer while she was sleeping. When Pallavi resisted with all her strength, the guard slashed her throat with a knife.
The 25-year-old daughter of senior Delhi-based bureaucrats died soon after.
The then joint commissioner of police Himanshu Roy had called this perversion of the highest order and deserves nothing but the death sentence.