In centuries past, the death penalty was a spectacle for the masses.
Four hundred years ago, those involved in the Gunpowder Plot - still merrily celebrated as Guy Fawkes Night - failed in their attempt to assassinate King James I and blow up Parliament. The culprits were dragged through London's streets to St Paul's churchyard where they were publicly hanged, drawn and quartered. Guy Fawkes himself managed to jump from the gallows and break his neck. He was lucky. His co-conspirators remained conscious through much of the ordeal, which included disembowelment and castration, their genitalia burned before the watching crowd.
Today's executions are meant to be more civilised, either carried out with clinical formality as in the United States, or in relative secrecy as in Japan and Singapore.
For the US, such clinical formality has become more difficult. The lethal injection method that is most common there relies on drugs that European manufacturers will no longer produce. It is also a process that many doctors will no longer supervise.
Last month, the US state of Oklahoma rejected a last-minute appeal by Clayton Lockett that had sought to disclose the source of the drugs to be used in his execution. His final moments degenerated into a gruesome farce. After taking nearly an hour to find a suitable vein, a needle was ultimately inserted into one in his groin. An untested cocktail of drugs was then administered. He was pronounced unconscious - only to start moving his body and rolling his head from side to side, mumbling incoherently. Prison officials hurriedly drew the curtains between the death chamber and the witness gallery. Half an hour after it began, the execution was called off. But Lockett was pronounced dead 10 minutes later - from a heart attack.
Reassessment in US and Japan
OKLAHOMA has now suspended executions for six months and President Barack Obama has ordered a review of how the death penalty is carried out in the US. It is possible that this could be a tipping point for capital punishment in the country. The number of executions has fallen by half since 2000, with half a dozen states abolishing it completely in the past seven years.
A similar debate is now under way in Japan, triggered by the release in March of Mr Iwao Hakamada. Sentenced to death in 1966, he was set free after DNA evidence favourable to him was finally admitted and the Shizuoka District Court concluded that other evidence in his original trial had been fabricated.
Though there are many principled reasons to question whether a state should take the life of someone who has been removed from the streets and rendered harmless, this tends not to be the way in which attitudes to the death penalty change. Instead, changes in public opinion are often driven either by revulsion at the manner in which executions are carried out or uncertainty as to whether an innocent person might suffer irreversible punishment.
How the issue is framed is important. Public support for the death penalty remains around two-thirds in the US, for example - but drops to half when there is an alternative of life without parole. It may spike when there is a heinous crime, but plummet after a high profile acquittal.
A moratorium in Singapore?
SINGAPORE is the only other industrialised country to retain the death penalty, though it is now more than three years since an execution was actually carried out. Legislative changes in 2012 significantly reduced the scope of the mandatory death penalty, long a target of criticism because it removed any discretion on the part of judges when it came to sentencing.
The Government was at pains to emphasise that this was not a change of policy and that the death penalty - including the mandatory death penalty - remained an option.
Nevertheless, all 34 people on death row at the time are having their cases reviewed to see if they could benefit from the changes.
Several have since had their sentences commuted to life imprisonment, sometimes with caning. (Caning itself is now the subject of a constitutional challenge. Singapore is the only advanced economy that retains judicial corporal punishment, though the number of persons sentenced to caning has fallen significantly since 2007.)
Singapore's Government is correct in responding to abolitionist critics such as Amnesty International by noting that international law does not forbid the death penalty as such. It is arguable, however, whether drug trafficking as defined in Singapore reaches the threshold of "the most serious crimes" for which the death penalty is to be reserved.
A United Nations General Assembly resolution calling for a worldwide moratorium on the death penalty has been slowly gaining support, rising in December 2012 to 111 countries in favour and 41 against. But it does not have the force of law.
Singapore can therefore choose whether to retain the death penalty, adopt a moratorium, or abolish it. In making that choice, the relative secrecy of executions and continued reliance on hanging mean that the type of debate presently roiling the US will probably not take place.
Unlike Japan, there does not seem to be a clear case of an innocent person condemned to death to rally an abolitionist campaign in Singapore.
Ismil Kadar is perhaps the closest, but his release after two years on death row pre-dates the 2012 reforms. An odd-job labourer with an IQ of 73, Ismil was released in July 2011 after he was cleared of murdering an elderly housewife six years earlier. In its judgment, the Court of Appeal issued a strongly worded judgment highlighting "serious lapses" by police and prosecutors. He is now back in prison for an unrelated crime.
Yong Vui Kong's case did garner significant public interest and support, but on the grounds of clemency rather than innocence.
In June 2007, at the age of 19, Yong was arrested in Singapore for possession of 42g of heroin. In November 2013 he became the first drug trafficker on death row to have his sentence commuted to life imprisonment.
Yet a third key argument may prove influential: whether the death penalty actually works.
Does the death penalty achieve its stated objective of deterring crime? The idea that it does has long been asserted in favour of capital punishment in the US and elsewhere - despite the fact that most studies show that the severity of penalties has little bearing on criminality. Far more important is the likelihood of being caught.
Indeed, in the three years since an execution was actually carried out in Singapore, there has been no appreciable increase in crime. In fact, statistics released in February showed crime at a 30-year low. The World Justice Project recently ranked Singapore second in the world for order and security as well as for criminal justice.
US judges abjure punishment
TWO decades ago, US Supreme Court Justice Harry Blackmun wrote a powerful dissent when the court refused to hear a routine death penalty case. Despite having upheld previous case law supporting its constitutionality, two months before his retirement he drew the line: "From this day forward, I no longer shall tinker with the machinery of death." He repeated his dissent in every subsequent death penalty decision.
More recently, retired Justice John Paul Stevens - another judge who upheld capital convictions through most of his career - published a book proposing six amendments to the US Constitution. One was aimed at outlawing the death penalty.
The death penalty can be an emotive and divisive issue. When considering the worst of humanity - such as the rapist of a child who kills his victim - it is easy to understand why many would call for the wrongdoer to be killed. Law Minister K. Shanmugam spoke to these feelings in his comments last weekend about such criminals.
But the purpose of a legal system, of the rule of law, is precisely to remove such passions from the administration of justice. All the more reason, then, to have a calm and rational debate before tinkering once more with the machinery of death.
The writer is dean of the National University of Singapore Faculty of Law.