Unfortunately this data doesn’t include any statistics of what happens when the investigators use a more efficient collection method, but it’s interesting data nonetheless. What we find significant is that by changing the collection method, particularly using wet-vacuum collection vs swabbing, the entire equation and ensuing results are dramatically affected and usually improved. Wet-vacuum forensic DNA collection is changing many outcomes and absolutely needs to be incorporated into every lab’s processes.
As the sensitivity of DNA analysis increases, scientists are able to develop profiles from ever-smaller samples of DNA. This has lead to testing of a wider array of samples collected from crime scenes, including window panes, bullets, hats and other clothing, cigarette butts, and many other items.
Attorneys sometimes ask me about the likelihood of obtaining a useful DNA profile from certain items of evidence. A study from six European forensic laboratories may give some idea of how likely it is to find a DNA profile on items commonly found at crime scenes. This article contains an interesting chart that lists the item and the likelihood of finding a full profile, usable partial profile, possibly usable partial profile, or no profile. It seems best to use this type of information as a rough guide, but it is interesting nonetheless.
It is important to keep in mind that as labs are able to…
View original post 112 more words