[VRWC_minion]

So they'll never be described as exact matches by the criminalists.....even if they share the same source? IE: blanket or towel? But the prosecution can say it?

My memory of the OJ trial is that days were spent discussing markers etc and theory on how the probility is determine. Never was it mentioned that anything was an exact match. They were always stated as probability. The same is true for fingerprints. Even though no two people have the same prints, comparing them requires matching between the two.

Its possible you could leave two fingerprints and that they cannot be matched to each other depending on the quality.

[Freedom2specul8]

That does ring a bell--..so it sounds like the jury needs to have that explained the way Lee or whoever it was explained it to the OJ jury..cuz I betcha it was explained. An educated jury is a fair jury...

probability webpage

[VRWC_minion]

Although forensic entomology can be very effective in determining elapsed time since death, it has its limitations :-

1. The temperature of the death site is obviously a very important factor, but few criminals are thoughtful enough to kill their victim right underneath a weather station! In most cases, the weather records come from several miles away. We are trying to overcome this by setting up a miniature weather station at the death site after discovery, to compare these data with that from the weather station, in order to determine the difference between the two sites, if any. Also the microclimate of the corpse itself will be slightly different from the surrounding area, especially if a maggot mass is present. Therefore, it is extremely important to know whether masses are present.
   
2. Forensic entomology in Canada is seasonal, that is, it is only commonly used in spring, summer, and fall when insects are abundant. It is of less use in winter, unless its very mild, as there are no or very few insects present. This can be a limitation, but can also be an advantage as I can sometimes show that a victim found in spring was killed the previous fall if insect evidence is present.
   
3. The results are not immediate, as it takes time to rear the insects. DNA evidence is now being developed to speed up identification of immature specimens.
   
4. The body may have been disposed of in a way that excludes insects e.g.

1. freezing - if the body was frozen for a period of time before being placed outside on, for example, 8 May, the insects would only invade then, giving the misleading impression that death had occurred on 8 May. However, other forensic experts would be able to determine whether or not the body has been frozen, and insect evidence will still determine time of exposure.
   
2. burial - if the body is buried deeply, then most insects will be excluded. However, most criminal burials are not very deep, as the aim is merely to conceal the body, and most insects will dig down to the body, particularly if there is blood soaked in the soil. Therefore, insect evidence can still be used. We have an estensive database for buried bodies in BC
   
3. wrapped - if the body is wrapped or packaged in some way the insects may be excluded, but the wrapping must be completely secure. A body part was found sealed in a garbage bag which had been tied securely at the top, but the remains were maggot-infested, and showed severe insect damage. The adult females had probably laid their eggs at the knot, and the minute first instar larvae had crawled in.

5. More research is needed. Insect succession varies from geographic region to region and the species and time of colonization must be developed for all areas using this type of evidence. Research has been conducted in British Columbia in a variety of habitats, seasons and geographic areas to develop a database for this Province. It is intended that this will be extended across Canada.
   
6. Drugs - the presence of drugs may affect the development of the insects. Work is planned to determine effects of common narcotics on insects in Canada