Wed, 22 Nov 2006
The Association of Chief of Police Officers (ACPO) published today the
DNA Good Practice Manual, Second Edition 2005. The following table from this document reveals that success rate in retrieving DNA from various samples is different in reality from what movies would make one believe:
| Evidence
types | Success rates |
| Semen
| 90% |
| Blood
| 87% |
| Chewing gum |
78% |
| Cigarette butts |
75% |
| Fingernail clippings |
69% |
| Comb/Razor
| 53% |
| Hair
with roots |
50% |
| Saliva
| 40% |
| Hair without visible
roots | 15% |
| Cigarette
lighter | 10% |
| Watch
strap | 8% |
Unfortunately this document includes other surprises such as the mention that DNA profiles in the NDNAD are not destroyed even when an profiled individual dies. I wrote more about this and some other aspects directly affecting me in a new
entry on the Innocent in London page.
