A recent double episode of Silent Witness has sparked controversy after a scene in the program prompted over 500 calls and emails from the public. However, it was a story consisting of a series of wild coincidences and complex red herrings that must be explained in simple terms in order to understand the context of the scene. (Contains spoilers)
Essentially it begins with a chief forensic pathologist who just happens to be driving back from the pub when he comes across a dying woman. This woman and her colleague (We'll call them victims 1 & 2) have been investigating a local prison, and have been murdered by the prison doctor (We can call him murderer 1) to cover up the fact that he was also paid to murder a paedophile/murderer prisoner (murderer 2 / victim 3) by the prisoner's sister (murderer 3). The doctor killed the paedophile using a drug patch prescribed to his sick daughter that the prisoner happened to be massively allergic to. However, he murdered the prison investigator and her colleague in a way that suggested it had been done by prison officers when they discovered what he had done.
Coincidentally, the head prison guard (murderer 4) then also murdered a prisoner (victim 4) and another guard (victim 5), to cover up a drugs ring; thus reinforcing the idea that he could have been responsible for the other murders. Also coincidentally, the guard used to be a policeman, and worked with the policewoman who happens to be investigating the crimes. And it seems while he was in the police he murdered an informant (victim 6) by beating him and repeatedly inserting a large pole into his rectum until he bled to death.
Oh yes, and the policewoman was there and witnessed it, but covered up the crime (Possible murderer 5 if the crime was considered a joint venture). And I almost forgot, the guard/policeman/multiple murderer also turns out to be the father of the policewoman's child. And sex partner to the wife of the guard he murdered.
Luckily, the pathologist's team get to process all the crime scenes even though they are involved, so rather than the police it's the pathologists who are able to break two murder cases and identify three murderers (although one, murderer 3, gets away with it). It seems that the police are all useless, corrupt and/or murderers and the prison service are all drug suppliers, crooked doctors and/or murderers. Luckily the forensic pathologists are there to discover crimes, follow suspects, stake out people's houses, do some pathology including illegal DNA testing, work out who did any murders and ensure that most of the guilty parties are called to account. All whilst flirting with various suspects, witnesses, victims, members of the investigative teams and each other.
Anyway, the reason most people contacted the BBC was to ask why the prison doctor (murderer 1) placed a white shirt button in victim 2's mouth, even though he wasn't expecting him to be there when he committed the murders.