Okay, let me try to summarise what I think is your argument, to make sure that I can address it as well as I can:
In my piece, I disputed Shanmugam’s claim that the death penalty is a deterrence to drug crime, and that drug abuse and drug-related crimes can be eradicated (or even substantially reduced) through the use of the death penalty. You said that I did not provide “hard cold evidence” that the death penalty does not work as a deterrence.
Here, I’ll take the opportunity to quote Roger Hood and Carolyn Hoyle from Oxford University’s Criminology department:
Because it would be morally repugnant to conduct random experiments in the use of capital punishment, it remains difficult — if not impossible — to find empirical data on the deterrent effects of the threat of capital punishment that would persuade a committed proponent of the death penalty to change their mind.
As far as some crimes punishable by death in several countries are concerned — such as importing or trading in illegal drugs, economic crimes, or politically motivated violence — there is no reliable evidence of the deterrent effects of executions. What evidence there is — which is mostly from the US — should lead any dispassionate analyst to conclude that it is not prudent to accept the hypothesis that capital punishment deters murder to a marginally greater extent than does the supposedly lesser punishment of life imprisonment.
Full link here: https://theconversation.com/there-is-no-evidence-that-the-death-penalty-acts-as-a-deterrent-37886
Also Jeffrey Fagan, another well-respected legal professor who has done plenty of research on the death penalty (including a comparison of Singapore and Hong Kong’s homicide rates):
Jeffrey Fagan, who provided expert testimony during a constitutional challenge against the death penalty in 2007, said drug offenders are prone to “hyperdiscounting”.
“Their reasoning in the face of threats of harsh punishment is skewed.”
If the death penalty did deter drug traffickers, it would suggest that supply would reduce in the particular country, pushing up prices. Drug use would then also fall.
But a study of the experience of Singapore, Malaysia and Indonesia between 1999 and 2005, a time when Singapore and Malaysia were executing heavily and Indonesia was not, shows that drugs were significant cheaper in Singapore and Malaysia Drug use also rose in both countries and remained more prevalent in Singapore than Indonesia.
“During this era, 73 persons were executed in Singapore [including more than half who were drug offenders], compared to two in Indonesia,” Kagan said. “Yet drug trafficking was increasing and drug prices were lower in Singapore.”
So yes, it is very difficult to say 100% that the death penalty does or doesn’t deter crime. What one can say is that the evidence suggests that capital punishment does not deter crime (be it drugs offences or murder).
My position, as well as that of other anti-death penalty advocates, is that due to the irreversible finality of a death sentence, the onus is on those who insist on executions to prove that these executions are actually working the way they say it does. Otherwise we will simply be hanging people based on unsubstantiated beliefs – how is that justice? How many people will be killed by state just because we think this works, with no conclusive, concrete evidence?
