Those who deal in drugs are certainly responsible for the deaths of many and the ruination of many lives. They may not be murderers directly, but many die because of them.
To treat them as being merely guilty of some minor crime is clearly wrong - they are not. But death... is still harsh in the extreme.
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I find Stone's argument far more compelling - although the difference between murder and killing is definitely a matter for debate. Where judge and hangman are acting to protect others (IE society at large), it would clearly not be murder.
Nonetheless to be directly responsible for the death of another human being must stain the soul.