As a former police photographer, it's fair to say that "Silent Witness" is very inaccurate when it comes to the "crime" work of the pathologists. They're only part of a team and the police would soon send them packing if they got involved like they do on the telly program.
The whole point of pathologists, soco and other civilian support services is to be "accurate and impartial". In other words you just report the facts. Once you start getting involved in investigating the case, the temptation to make the evidence fit your theory would be overwhelming.
Whoever writes "Silent Witness" seeems to be promoting the pathologists as far, far more important in an investigation than they really are.
I know that a bit of artistic licence is needed to make good television but wheras "Waking the dead" and "New Tricks" are also about ficticious departments, they still keep within the bounds of possibility. Silent Witness is way, way off track.