The Gamdevi police are relying on forensic tests to nail the woman who allegedly plotted an attack on her mother-in-law and sister-in-law.
The police had arrested Rupal Gandhi and her domestic help Ramchandra Gomane after Ila, 62, was killed and her mother Champaben 78, was injured in an attack at their flat in Sunita Apartments at Grant Road on November 14.
"Rupal is changing her statement regularly, hence we are waiting for the forensic report to confirm the truth," said PSI Rajendra Bhosale, investigating officer of the case from Gamdevi police station.
Rupal had allegedly paid Gomane to kill both women so that she could get a two-bedroom hall kitchen flat at Peddar Road.
"We have verified the documents and found that the flat was jointly registered in the names of Champaben and Rupal," said a police officer on condition of anonymity as he is not authorised to speak to the media.
"This means that Champaben's death would automatically result in the flat's ownership being transferred to her."
Bhosale said Rupal had given Ila an increased dose of medicine to make Gomane's task easy. "Ila suffered from schizophrenia, so her medicine was generally added to her food. On November 14, after giving Ila the drug-laced food, the accused left with her husband Deepak to attend a function in Matunga."
The police suspect that the increased dosage had weakened Ila and thus decreased her power to fight Gomane when he assaulted her an hour later.
"The forensic report will confirm whether Rupal had given Ila a heavy dosage of her medicine," Bhosale said.