In clockwork fashion since 2008, the United Nations General Assembly has deliberated every two years the question of a moratorium on the use of the death penalty, with a view to abolishing it. As the death penalty remains in our statutes, Singapore is a prominent retentionist state in the serious debate on the death penalty.

Last month, Foreign Minister Vivian Balakrishnan put forth Singapore's "contrarian views" on the death penalty at a high-level side event at the assembly.

Noting that the debate is a "heated, painful and emotional one", he affirmed Singapore's belief that "all human life is sacred" and the paramount objective to protect all human life.

Like his predecessor in 2014, he posited that the relevant question in the debate on the death penalty was "whether in very limited circumstances, it is legitimate to have the death penalty so that the larger interest of society is served".

Thus, the rights of the offenders must be weighed against the rights of the victims and their families, and the "broader rights of the community and society to live in peace and security".

Dr Balakrishnan stated that capital punishment for certain drug-related offences and for murder is a "key element" in keeping Singapore drug-free and safe. He reiterated that every state has the sovereign right and duty "to decide for itself what works, and to take into account its own circumstances".

Singapore's position on the death penalty is more nuanced than the abolitionists' austere characterisation of states that retain it as essentially having an abiding commitment to the death penalty. In 2012, Parliament made significant amendments to the Penal Code and the Misuse of Drugs Act, marking a shift from the longstanding mandatory to a discretionary death penalty system.

In murder where the killing was unintentional, the court has the discretion to sentence the accused to death or life imprisonment. The court may also order caning in cases where the sentence is life imprisonment.

Similarly, the Act provides that if a person was convicted of drug trafficking, the death penalty would not be imposed if two conditions are fulfilled. First, he must have only been a courier, not involved in any other activity related to the supply or distribution of drugs. Second, he had substantively cooperated with the Central Narcotics Bureau, or he has a mental disability, which substantially impaired his appreciation of the gravity of drug trafficking.

These amendments do not lessen the severity of drug trafficking offences. They, however, recognise that couriers, a crucial part of the illicit drugs supply chain, are morally less culpable than the drug syndicate leaders who direct drug couriers. Executing drug mules will not deal with the root causes of the serious crime of drug trafficking.

The Government has determined that the mandatory death penalty (MDP) may not be needed for all types of serious crimes. This is an important first step, notwithstanding the attraction and force of the MDP was its unequivocal demonstration of zero tolerance and resolve in maximum deterrence.

Yet, the shift to the discretionary death penalty regime should not be misconstrued as Singapore letting up on drug trafficking and murders. Instead, this shift was necessary to retain public confidence and legitimacy in our administration of criminal justice.

Giving our Supreme Court judges the discretion in sentencing empowers them to weigh the relevant factors and the mitigating circumstances, and to individualise sentencing. By tempering justice with mercy, the punishment meted out can better fit the crime, and offenders given a second chance in appropriate cases.

To be sure, there are increasing - and more strident - calls for the complete abolishment of the death penalty. In the past few years, the UN Special Rapporteur on torture and other cruel, inhuman or degrading treatment or punishment has urged UN member states to consider whether the death penalty fails to respect the inherent dignity of the person, causes severe mental and physical pain and suffering, and amounts to torture or cruel, inhuman or degrading punishment.

Singapore has rejected the link between the death penalty and torture, cruel, inhuman and degrading treatment.

The European Union and the UN have called for a moratorium on the use of the death penalty. The moratorium has gained traction, as shown by the voting records at the UN assembly. In 2014, the draft on the moratorium on the use of the death penalty was adopted with a recorded vote of 117 in favour to 37 against, with 34 abstentions. In 2012, it was 110-39-36. In 2010, it was 107-38-36.

Singapore has consistently voted against the resolution on the moratorium on the use of the death penalty.

Besides Singapore, the list of retentionist states include Afghanistan, China, India, Iran, Japan, Malaysia, Saudi Arabia and the United States. Nevertheless, Singapore has not ignored or disregarded the international developments. While there is still no international consensus against the death penalty, the list of abolitionist states grows slowly but surely, suggesting that there might be inexorable movement towards its abolition.

Singapore's execution figures have declined significantly since the 1990s but the overall crime situation has not worsened; in many respects, it has improved. Could our tough stance on crime continue to work well without the death penalty?

Given the conflicting empirical data elsewhere, however, both abolitionists and retentionists have immense difficulties proving their case persuasively and compellingly. Statistics alone will not resolve the deep divide between the two camps.

The Singapore Court of Appeal has consistently ruled that the MDP is constitutional and not in breach of the fundamental liberties guaranteed by the Singapore Constitution. On whether capital punishment legislation should be modified or repealed, it took the view that these "policy issues… in the exercise of its legislative powers… is for Parliament, and not the courts, to decide on the appropriateness or suitability of the MDP as a form of punishment for serious criminal offences".

I regard the discretionary death penalty regime as a determined expression at maintaining the legitimacy of our capital punishment regime. More significantly, it manifests our ability to get out of the force of habit, convenience, and reliance on our long-held dogma that the MDP is necessary to deal with the most serious crimes.

There is, as yet, no public clamour in Singapore for abolishing the death penalty. While there is no authoritative study on public attitudes towards the death penalty, various past surveys point to support for its retention. There appears to be healthy public trust and confidence that the death penalty regime in Singapore has the requisite deterrent effect on criminals and has sufficient safeguards.

Nonetheless, the authorities face the continuing imperative of demonstrating that the death penalty regime works well and is in accord with societal values and norms. In this regard, we must not lose sight of the value and sanctity of life even as we calibrate the appropriate balance of rights and responsibilities between those who commit serious crimes, and the victims and their families, and the rest of society.

Regular and robust reviews are necessary to evaluate the need and use of the death penalty as an integral part of the administration of criminal justice in Singapore.

Our no-nonsense approach towards crime has made security and order defining features of our society.

Keeping our criminal justice system relevant and legitimate in the face of changing realities and the rapidly evolving crime situation is vital in maintaining public confidence, while also keeping faith with the values that Singaporeans regard as important.

•The writer is associate professor of law at the Singapore Management University School of Law.