In the past two years, the Maharashtra Forensic Science Laboratory (FSL) has received over 1,815 DNA samples of 'probable suspects' in the rape and murder of minor girls from Nehru Nagar in Kurla (East) and Cuffe Parade in south Mumbai.
Sources said the random DNA tests being carried out are an indication that the police have no concrete line of investigation. Also, it is going to put a dent of Rs90 lakh on the state exchequer.
Three girls were raped and murdered in Nehru Nagar in 2010. Cuffe Parade and Colaba have also witnessed three such murders since last year.
However, only one case in Nehru Nagar has been solved with the help of DNA profiling. The police arrested Javed Shaikh, 19, after his DNA sample matched with a hair strand found near the body of the third victim, Nusrat Shaikh, 8.
The south Mumbai police are also hoping to strike gold with the help of the sperm samples they found near the body of the second victim, Karishma Vijay Chavan, 3, which was found in January near the Nariman Point fire station.
An official from the FSL said: "A single DNA test costs around Rs5,000. The Nehru Nagar police have sent us at least 1,000 samples and the south Mumbai police have sent 815 samples."
He added that 650 reports had been sent to the Nehru Nagar police and reports of 140 samples were sent to the Cuffe Parade and Colaba police.
"But the DNA samples continue to come even now. When any arrests are made in either of the two cases, we check them on priority basis and send the report at the earliest," the official said.
On March 15, the Cuffe Parade police detained Mohan Yadav, 32, for allegedly trying to kidnap a three-year-old girl. They suspected that Yadav was involved in the murder of Chavan and the two other girls as his appearance matched the sketch of the accused. "But his DNA did not match," the official said.
According to former IPS officer-turned-lawyer YP Singh, the police were conducting mass DNA tests on suspects without any concrete proof.
"Mere suspicion cannot be a basis for conducting tests. Scientific tests should be done only after zeroing down on the suspects," he said, adding that that the people, whose reports had come negative, could even can approach the human rights against this.
Lawyer S Kunjuraman told Hindustan Times, "Police don't want to use basic investigation techniques. They should know that a criminal would never commit a crime and wait to get arrested. Random DNA testing will not result in anything and they should understand this."