The passage of time can both pose challenges to investigators and benefit them.
“Physical evidence may degrade and be lost. Potential witnesses may move away and finding them may become difficult. In some cases persons with knowledge may pass away and their information is lost to us permanently. Memories may also fade, making the gathering of evidence from witnesses more difficult,” Krygsman wrote, adding scientific advances are constantly being made.
“In London, investigators often review the evidence collected in unsolved homicide cases to explore the possibility that new and improved forensic testing techniques could yield results that can be used to advance investigations.”
Arntfield, who penned a best-selling book on unsolved London-area killings, praised city police for achieving a perfect homicide clearance rate during the past eight years, noting the median rate for solving such crimes in American cities is just 66 per cent and dips as low as 11 per cent in some places.