When the implication of "intention" is used to define an element of actus reus and mens rea combined to prove if historically in the past physical actions were punished more than failure to acts. Liability for an act requires it to be proven that the actor had mens rea or the intention of causing harm or damage, yet it can be ascertained that for many criminal omissions the mens rea is the same, in that they know by not acting, harm or damage may still occur. It is thus questionable whether there should be such a clear distinction between the two.
This may be exemplified by Fagan v Commissioner of Police Of the Metropolis  where an originally accidental act of driving a car onto the foot of a police constable was then followed by the intentional mens rea resulting in a temporary refusal to remove the car from the foot. This element of mens rea adapts the incident, in the eyes of the law, to have become one long sequence of events, which technically since the actus reus and the mens rea would serve as proof, under normal circumstances as a criminally liable act.
This suggests that the defendant was punished for an act of omission. However to find if omission was being punished more now than it was historically we have to look at evidence of where it has been used. Most of the cases I found were of more recent times, e. g. Reflecting on the case of Airedale NHS Trust v Bland  where doctors of the hospital requesting permission to remove life- supporting machines brought a request to court. Lord Goff of Chieveley, in the House of Lords, ruled that it would be a legal omission due to the situation, as there was no duty for a doctor to prolong the life of an individual regardless of the circumstances. However, contrary to Lord Goff's ruling it could also be viewed that the action was indeed an act of murder, the reason for this was because the doctor indeed knowingly knowing what would happen due to his actions complete with the necessary mens rea and actus reus.
However, Historically in the past physical actions were punished more than failure to act (Omission) but in recent times things have began to change and we have started to punish more failure to acts, I can support this statement because most of the cases I looked into were of more recent times where they punished for failure to act.
As it does serve to distinguish and highlight some behaviour that can only be solely classified as an omission to act, It clearly states in the cases I looked at above that failure to act is punished much more and the courts will look at it in more depth then they would in the past.
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