On November 3, the 29th day of Abby Choi’s murder trial, prosecution DNA expert Dr Wai Wing Kong told the court that a single-source DNA profile recovered from a hammer handle matched Choi’s former husband at all 26 loci. He said the profile could have come from him, while comparisons excluded the other two defendants’ profiles. All three defendants deny murder.
Dr Wai put the random-match probability at one in 6.2 billion, on the condition that the DNA did not come from the former husband. The figure describes the chance that an unrelated person would have the same profile. It does not measure the chance that the former husband left the DNA or his probability of guilt.
Dr Wai also said DNA transfer to an object required force or friction and some time. A brief, ordinary touch would not be enough, he told the court.