... and to refresh my memory, I went looking for the background on capital punishment there in relation to that case. Tim Evans was an Irishman, of not much smarts, who was arrested for killing his wife and daughter and was convicted and hanged in 1950. It was a highly publicized crime and public sentiment ran very high for conviction because it was particularly brutal. Three years later, a neighbor by the name of John Christie was found to be a serial killer of children and was actually responsible for the crime.
But, in the course of reading up on that case, the article also mentioned some data in England which seemed to fly in the face of the conventional wisdom in this country that the death penalty served as a deterrent:
"The {1965 Murder}Act included an amendment introduced by Henry Brooke, the previous Conservative Home Secretary, to the effect that it was to expire in five years unless both Houses voted to keep it permanent. After four and a half years it was inevitable that the experiment had been a success. Murders were continuously decreasing during an era that saw a considerable rise in other forms of violent crime, and although there had been an increase in murders by shooting, there had also been a similar increase in suicides following those murders."
The 1965 Murder Act abolished capital punishment for all but two crimes--high treason and piracy on the high seas. The business about shooting mentioned above is relevant in that an earlier law in 1957 restricted the death penalty to cases involving murder during theft and murder by shooting (or by explosive device) and a few other conditions, so that someone who killed with a knife could not be sentenced to death, even if the crime was premeditated, but someone who shot someone, even without premeditation, was required by law to be hanged.
It's interesting that the suicide rate of the murderer, after the introduction of the 1965 death penalty ban, may have increased with the prospect of spending a life in prison.
http://web1.pipemedia.net/~sar/bentley/cp-uk.html