Chapter 6

All About DNA

Forensic results

D1 and D2 did not seem at all fazed when interviewed by the ICAC officers. They remained irresponsive and stayed silent when asked to give an account of the HK$50,000 seizure.

In this case, without any direct evidence to prove D1's HK$50,000 banknotes were from D2, the cash and envelope seized from D1 upon arrest became crucial circumstantial evidence.

According to the Government Laboratory's forensic analysis, DNA mixtures mainly from D2 were found on the surfaces of the envelope and the banknotes.

The ICAC reckoned that the HK$50,000 was manifestly a bribe from D2 to D1.

In accordance with the Independent Commission Against Corruption Ordinance (ICACO), an authorised ICAC officer may require a swab sample taken from the mouth of a suspect for comparison with the genetic information derived from forensic analysis. In this case, the ICAC required both defendants to provide their samples.

"We compared the DNA collected from the surfaces of the envelope and the banknotes to the DNA sequences of the two defendants, and found a large amount of D2's DNA and traces of D1's DNA thereon." The case officer recalled, "D1 deposited the banknotes into his bank account, so we seized the banknotes and sent them over for forensic examination. As a result, D2's DNA was detected on the banknotes. However, as the banknotes had been processed by an automatic teller machine and kept in there for quite some time, only a small fraction of DNA could be detected.

Under the ICACO, the ICAC is vested with investigative powers to fight corruption, including the power of taking a non-intimate sample from a person for forensic analysis.

Section 10E of the ICACO stipulates that the ICAC may take a non-intimate sample (such as a sample of head hair, a sample taken from a nail and a swab taken from the mouth) from a suspect being detained at the offices of the ICAC for forensic analysis purposes.