WHAT IS A CONTROLLED DRUG?
A controlled drug, as specified in the First Schedule of Singapore’s Misuse of Drugs Act, is any substance or product which is for the time being specified in Part l, Il or Ill of the First Schedule of the Act or anything that contains such substance or product. The substance can be natural or synthetic and is used to produce a specific physiological or psychological effect. Heroin and methamphetamine remain the top two drugs of choice in Singapore, with more than 90% of drug offenders arrested in 2013 and 2014 having consumed one of these drugs.
CLASSIFICATION OF CONTROLLED DRUGS
The common drugs of abuse fall into four categories:
COLLECTION OF DRUG EVIDENCE
Drugs may be seized in cases related to drug consumption and trafficking, robbery, homicide and sexual assault. Drug evidence exists in many forms, such as tablets, capsules, white powders, syrups, solutions, plant material, drug paraphernalia or drug precursors at a clandestine laboratory site. For cases involving drug consumption, urine, blood or hair samples can be collected from the individual.
LABORATORY EXAMINATION OF DRUG EVIDENCE
The objective of laboratory examinations is to determine whether the submitted sample contains controlled drugs, followed by ascertaining the types, purity and amount of controlled drugs present. Based on the results of the analyses, law enforcement can decide whether to pursue criminal charges, and the court can determine guilt and appropriate sentencing for individuals suspected of drug-related crimes.
For drugs of abuse cases, interpretation of laboratory findings has to take into consideration the different possibilities for the presence of a controlled drug. Besides the analytical techniques used for drug analysis, the scientist has to be familiar with the pharmacokinetics of each type of controlled drug.
SCREENING & CONFIRMATORY TESTS FOR DRUGS
General techniques for examining commonly encountered drugs are outlined below. Two main types of tests are used: screening tests provide quick answers, giving an indication of the type of controlled drug possibly present but they are unable to conclusively identify the drug. Confirmatory tests are more specific and can determine the precise identity of the substance as well as quantitate the amount of drug present.
- Macroscopic examination of the drug packaging, gross characteristics such as the shape, colour of the drug are described and the drug weighed.
- Screening tests such as colour spot tests, immunoassays and thin layer chromatography (TLC). Colour tests will indicate the presence of a controlled drug by changing to a particular colour.
- Confirmation of controlled drugs is a multi-step process using analytical techniques (gas chromatograph and liquid chromatograph, each coupled to a mass spectrometer, i.e. GC-MS, LC-MS) to separate the individual substances in the sample to determine their chemical characteristics, and compare them against reference standards to make a positive identification. This is usually followed by quantitative analysis of the sample to determine the amount, or purity of the controlled drug(s).
WHAT OUR EXPERTS DO FOR CONTROLLED DRUG CASES
A prerequisite for efficacious case preparation is capturing the essence of the forensic report, and understanding the significance of the evidence in relation to the context of the case. TFEG’s experts can help you better understand the scientific terminology, laboratory processes, procedures and analytical methods, and interpretation behind the forensic drug report. As Court-tested forensic experts with many years of experience in developing and applying forensic techniques in Singapore, we are thoroughly familiar with the strengths and limitations of analytical methods, the interpretation of data, and the significance of findings.
For drugs of abuse cases, if your client is adamant that he did not consume a controlled drug although his urine sample tested positive, it is time to look for TFEG. Let us help you find out the reason for the positive result.
OUR PAST CASES
Controlled drugs analysis is often associated with the examination of bulk specimens from drug seizures and urine specimens from drug abuse suspects. Other types of evidence submitted for drugs-related cases include the following: (click on each title to read more)
During collection of urine specimens at CNB, drug abuse suspects have tried to evade detection by wetting their pants instead of urinating into the bottles. Our experts examined these garments for the presence of urine and controlled drugs. In one of the cases, a mixture of morphine, methamphetamine and codeine was detected on the damp shorts and underwear. In another case, mono-acetyl morphine, morphine and codeine were detected on the damp shorts and jeans.
TFEG was engaged to provide consultancy on whether medications prescribed to our client contained methamphetamine or compounds that could metabolise to methamphetamine. Our findings indicated that the prescribed medications were not the source of the methamphetamine detected in her urine specimens. After the client mentioned that she consumed health, dietary and sports supplements daily, TFEG requested for a list of these supplements. One of the sports supplements was analysed and found to contain methamphetamine.
It is not uncommon to find gas cylinders, measuring devices and unknown liquids in locations suspected of illegal growth of cannabis plants. In a case where evidence was recovered from a private apartment in Singapore, our expert determined the contents in the gas cylinder, functionality of the measuring device, and chemicals in the unknown liquids. Our findings were useful in assisting the investigator establish the suspect’s intent to grow cannabis indoors.
Drugs are often packed in re-sealable plastic bags, plastic straws or other packaging materials for trafficking. Plastic bags, newspapers, and adhesive tapes such as duct tape and electrical tape are commonly used to wrap drug packages, which are then concealed in inconspicuous parts of vehicles, and modified suitcases with hidden compartments. Locally, our experts pioneered the forensic examination of manufacturing marks on mass-produced packaging products. One case involved drug evidence in straw sections recovered from two suspects who insistently denied association with each other. However, our analysis revealed that the packaging materials containing the drugs originated from the same source. Such evidence plays a crucial role in linking suspects, especially when packages are empty or have no DNA evidence.
Five Nepalese and three South Koreans were arrested in 2009 on suspicion of roles ranging from drug couriers to drug associates and drug coordinators. Shoes, shoe polish, shoe brush, masking tape and other physical evidence were recovered from the rooms occupied by the two groups of nationals in different hotels. Our expert reconstructed the sequence and manner by which the drugs were packed, transferred and repacked in the shoes worn by the suspects, thus providing evidence associating the various suspects to the different locations, their relationship with one another and the roles they played in the international “master plan’.
To find out more about controlled drugs analysis and its interpretation, read our article “Controlled Drugs” featured in the July 2016 issue of the Singapore Law Gazette.
Please call us at 6459 0494 or email us at enquiries@forensicexperts.com.sg.