The law of homicide in England and Wales has been criticized for a long time before it finally underwent reform. In 2006, the Law Commission stated that some provisions of the legislation have not changed since the seventeenth century. The basis of the law appeared outdated as even previous reforms made by Parliament could not stand the pressure of the legal changes.
According to the Law Commission, it is important to create a new three-tier structure of the homicide offenses instead of the traditional murder/manslaughter differentiation. The new system proposed by the Commission included first-degree murder which required a mandatory life sentence and second-degree murder alongside with manslaughter which shall undergo discretionary life sentence. The first-degree murder was defined as killing with the intent to cause serious injury with the awareness of probable death.
The Law Commission suggested that parts of homicide law which concerned provocation, diminished responsibility, and complicity also shall be changed. Self-defense, under the new classification, is counted as a manslaughter instead of a murder. Killing in response to a big provocation or fear of a serious violence would reduce the conviction to manslaughter as well. Diminished responsibility could also include mental abnormality which arose out of the diagnosed condition or developmental immaturity.
The government, in their turn, decided not to proceed with as many changes as the Commission have proposed. Many provisions were rejected, however, the self-defense law was indeed changed. Loss of control partial defense was created under the Coroners and Justice Act 2009. Adherents of the reform proposed by the Law Commission suppose that the changes made by the government will make it more difficult for women victims of domestic violence to gain the partial defense.