Manu Sharma, who killed his wife, his two children and himself in the southern state of Gujarat in 2016, was an Indian Police agent, his lawyer has said.
Manu Sharma was a member of the Mumbai Police Force (MPF), and had been deployed in the state for six years.
In the past few years, he had worked for the agency as an agent, said his lawyer Shashi Kaul, who is also a BJP leader.
“He was a very good man, who was committed to serving the people of Gujarat,” Mr Kaul told AFP news agency.
“His wife was a good person and had a good heart.
Her life was well taken care of,” Mr Sharma said.
The two children, ages 2 and 7, were shot in the head.
They were shifted to the National Medical College Hospital in Ahmedabad, where they died on Tuesday.
The father was admitted in a critical condition, but he succumbed to his injuries on Wednesday morning.
The woman was rushed to a local hospital, where she was pronounced dead.
In December, police found a note written in Hindi in the home of Manu and his wife.
In it, he said he had a son who was an employee of the agency, and that the family was not planning to sell the property.
He also claimed that he had recently been transferred to a police station in Gondia, the state capital, and was not in touch with his family.
The police said the family had a history of “incidents of domestic violence” but refused to comment on the allegations.
Manus Sharma’s wife and son, both aged two and seven, were killed on June 30, 2016.
He has not been charged with any crime.
He was arrested on July 9, and has since been charged under various sections of the Indian Penal Code.
His lawyer said the “vast” amounts of money he has received for his legal defence amounted to Rs3.4 million.
Mr Kaul said that the police had been asking for Rs2.7 million from the family for bail and were preparing to take a plea against him.
The MPF has said the charges against the officer have been dropped, and Mr Sharma has been discharged from the force.