In a murder case, they will be asked to comment on the time of death, cause of death, and whether the injuries inflicted on the victim by the accused were an operative cause of death. This will include detail concerning any weapon that has been recovered as well as splatter marks on the clothing of the defendant if the victim has bled in the attack. A lot of murders are usually through stab wounds and the experts can tell from the splatter pattern on the clothes of the accused where they were stood in relation to the victim at the time of the killing.This evidence can lead the doctor to be able to draw a conclusion about whether the killing was a result of self-defense or whether the attack was a prolonged and sadistic attack. Both the body of the victim and that of the accused will be scrutinized and the experts have the ability to decipher whether any bruising on the accused bolsters an argument that they were being attacked and that they were acting in self-defense when they maimed or killed the victim. The responsibility of experts in these matters can be a little daunting as a misread post mortem or analysis of bruising on a body might lead to the wrongful decision4 that the accused was acting in self-defense when he killed the victim.Given that juries are often swayed by expert opinion as to how any injury might have been caused it would seem fair that anyone holding themselves out to be an expert should be liable if they make a mistake5 as to the cause of an injury6. The degree of responsibility and the punishment they could face is questionable since they are only offering an opinion. In the light of recent issues surrounding expert evidence and the quashing of the convictions against Sally Clark7 and Angela Cannings, it seems obvious that too much reliance is often placed on expert evidence as without the statement from Sir Roy Meadow those accused might not have been found guilty.