Solving crime with science

By HARIATI AZIZAN

The proposed DNA Identification Act will enable the police to establish a DNA databank that can help solve crime investigations. But how will it help fight crime?

"DNA can be extracted from any biological specimen. Just a strand of hair will do, but under the present law, we need consent" Hithaya Jeevan

DURING investigations on the rape and murder of a schoolgirl in 1999, Police hauled up a total of 22 suspects.

For each suspect, forensic scientists had to conduct individual tests to match the person’s DNA with the different DNA samples found at the crime scene manually. Then it took more than a week to analyse a DNA sample and a few more days to compare the analysed DNA data with the information in police files.

“The whole process was time consuming,” deputy director general (policy) of the Chemistry Department, N. Hithaya Jeevan, said, recalling his most unforgettable case.

“If we had had a DNA database then, it would have really helped speed up the investigation,” he added.

Think of what has become the standard scene on TV and in the movies: one test and a mere click is all that is needed to search for a match on the computer.

“With a national DNA databank, the profiles of criminals and suspects can be recorded. Special software can compare the DNA found at the crime scene, or the DNA stains, with the data in the computer system. If there is a link, police can bring the suspect in and investigate further,” Hithaya Jeevan continued.

Alas, after all the testing, none of the DNA of the 22 suspects matched any of the crime stains. With no other leads, the case remains unsolved.

And it is one among many still unsolved today.

According to Minister in the Prime Minister's Department Datuk Maximus Ongkili, in January last year, our police's solving rate was 50%, compared to the Interpol’s solving rate of 22%.

Having a national DNA databank will improve the police’s solving rate further, noted Deputy Internal Security Minister Datuk Fu Ah Kiow: “A DNA databank will help police use forensic science to solve crime. As DNA data is conclusive, it will also help strengthen the case in court.”

This is something his ministry is hoping to kick off with the proposed DNA Identification Bill.

According to Fu, the final draft has been submitted to the Attorney-General's office where it is being finalised. It is hoped to be tabled in Parliament at its next sitting.

Scientific clue

DNA, or deoxyribonucleic acid, is the chemical blueprint for a person’s biological make-up and is different from person to person. Only twins might share the same DNA. Used for identification, it is 99% accurate.

According to the Locard Exchange Principle theory, it is almost impossible to commit a crime without leaving behind some DNA stains such as blood, saliva, vomit, bone and tissue. Hence, forensic scientists use these DNA stains to identify a perpetrator. The process is called genetic fingerprinting or DNA profiling.

Currently, the Chemistry Department has compiled a database of crime stains from unsolved cases. However, there is no law to enforce suspects or convicted criminals to give their DNA to the police, what more to allow the authorities to keep their DNA data.

“DNA can be extracted from any biological specimen given by the suspect or convict. Just a strand of hair will do, but under the present law, we need their consent,” Hithaya Jeevan explained.

According to experts, repeat offenders commit 30% to 40% of crimes and there are many who migrate from minor crimes to more major crimes, he continued.

“However, each time there is a crime, we get new DNA stains from the scene and don't have anything to compare them with.”

Fu agreed that the possibility of solving past unsolved crimes would be higher with a national DNA database, especially if the criminal was a repeat offender.

This has proven successful in countries with national DNA databanks, he added, such as the landmark case in the United Kingdom, where a burglar raped an 11-year-old and indecently assaulted a nine-year-old in 1988. Semen was found at the scene but police could not identify the assailant. However, the case was solved 13 years later when a 59-year-old man was arrested for shoplifting in another town. When his DNA profile was run through the UK's DNA databank, it was found to match the DNA stains from the scene of the earlier crime. The shoplifter admitted to the crime and was charged.

Citing the Nurin Jazlin Jazimin sexual assault and murder case, DNA analyst at the Forensic Laboratory, Royal Malaysia Police (RMP) ACP Mohd Abdul Aziz said it would also allow the police to link a new case to other cases for leads.

“It would help in police investigation to see if it was committed by a serial criminal.

“Otherwise, it would be left to police's hunches and manual investigation by digging up old or other files.

“For example, with a National DNA database we could have made a more concrete link between the Nurin case and the Kampung Baru molester,” he said.

DNA tracking is now compulsory for all violent crimes. However, even with a DNA match, further police investigation is needed before the suspect can be convicted, Hithaya Jeevan highlighted.

“After the suspect is taken in, you will first need to repeat the test – take the sample again and analyse the data. The DNA database is only a tool for investigation. It does not establish innocence or guilt.”

ACP Mohd concurred.

“DNA evidence can only prove who was there at the crime scene. Other corroborative evidence is needed to implicate the suspect of the crime,” he said.

A problem may arise, he highlighted, if no DNA stains are found at the crime scene.

For cases like car theft or snatch theft where the likelihood of evidence being left at the crime scene is low, DNA cannot be used to solve them.

“We look for shoeprints and things dropped but most of the time the evidence is driven away. Currently, car theft and snatch theft are the highest number of crimes committed and the lowest number to be solved,” he added.

Outwitting the police

Another growing problem he highlighted is how criminals are learning to outwit the police with technology. They are learning things from TV and films, he said, adding that it is becoming common for criminals to leave behind DNA of other people such as used cigarette butts or hair follicles to mislead the police.

They are also becoming more sophisticated in covering their tracks, he said, citing burning of victims such as in the high-profile Canny Ong case or the blowing up of the victim, such as the Altantuya murder case.

“What they don’t realise is that the forensic lab now has the technology and equipment to handle contaminated samples like this,” said Hithaya Jeevan.

For example, if the body is totally burnt, making it difficult to obtain skin, hair or blood samples, the marrow from the femur bone can be taken for analysis. If the teeth are still intact, they will be compared with the victim's dental records.

Analysis can be done even with microscopic samples, said ACP Mohd.

He added the police work hard to stay one step ahead of criminals.

“There is a lot of information circulating about DNA and new technology but we also do a lot of research at the lab to detect criminal trends and developments,” he said.

While having a national DNA database will not guarantee a lower crime rate, he said, it might deter repeat offenders, as well as first-time offenders, from committing a crime.

But Fu stressed that to effectively fight crime, everyone needs to get involved.

We all need to work together to raise public awareness and prevent crime. It is everyone’s responsibility, he reminded.

- The Star