The execution of the ringleaders of the so-called Bali Nine gang of drugs smugglers, Andrew Chan and Myuran Sukumaran, and six other people - nearly all of them foreigners - convicted of drugs smuggling in Indonesia has in recent months become the focus for anti-death penalty campaigners. One Filipino woman was apparently not among those executed by the firing squad. The Bali Nine case demonstrates more than any other why the death penalty should be outlawed worldwide.

As Amnesty International puts it, the death penalty violates the right to life and is a "cruel, inhuman and degrading punishment." It is not only a question of what method of execution is used, but also the mental pain and suffering prior to the execution.

Those executed a few hours ago have been subjected to months of mental pain bordering on torture, as their cases moved through the courts. Prior to the execution, they were even denied spiritual support of their choice. Just what their families have endured and will have to endure in future is indescribable.

There is also the question as to whether the punishment fits the crime. As the UN has pointed out, the death penalty continues to be imposed not only for treason or murder but also for offenses like drugs smuggling which do not meet the threshold of serious crime for which the death penalty can be imposed under international law.

The whole point of a punishment is that it must be seen to have an effect. Chan and Sukumaran, for example, were convicted of smuggling drugs from Indonesia to Australia 10 years ago. Prison has by all accounts changed them. They have admitted their crimes and sought atonement and forgiveness. The fact that they had sought to rehabilitate themselves was ignored completely by President Widodo when he rejected their appeals for clemency.

This illustrates that the motive for the imposition of the death penalty for drugs offenses is political. It is not about rehabilitation. Widodo has spoken of the drugs crisis in Indonesia. But he continues to ignore the fact that it has been proven over and over again that the death penalty does not work as a deterrent. Has drug smuggling ceased in Indonesia since the death penalty was imposed? No, it has not. In fact it is increasing. The real problem is widespread poverty. That is what needs to be addressed, and that is a far more challenging proposition than shooting people.

Widodo has not only failed to come up with an effective plan to tackle the drugs problem in Indonesia so far. He has used these executions and the threat of more to follow as a diversion so that he can indulge in political grandstanding and play to nationalist sentiment. Despite pressure from the opposition, Widodo, Indonesia's first president to be untainted by the years of the Suharto dictatorship, had a unique opportunity to establish himself as a politician who was willing to put the country's human and civil rights record straight. He could have done this either by extending the five year moratorium on the death penalty - ended by his predecessor in 2013 - or by abolishing it altogether.

Instead he has fallen into the trap of believing that by refusing clemency to those on death row for drugs offenses he is proving to be a tough guy, someone his opponents in Indonesia's corrupt political system have to take seriously.

To stand any chance of winning that argument he needed a fair and just judiciary. One of the strongest arguments against the death penalty is that judicial systems are error-prone and that often the accused cannot be guaranteed a fair legal process. In the last few days, a former defense lawyer has revealed what was going on behind the scenes at the Bali Nine trial. Judges - it is alleged - demanded $130,000 dollars for a 20-year jail sentence instead of the death penalty. That is apparently the price of the life of a foreigner in Indonesia. Later, other officials at a higher, semi-political level allegedly intervened in the proceedings and demanded that the death sentence be imposed regardless of the court's proceedings.

All of this makes a mockery of justice in Indonesia and underlines once again that the death sentence is more likely to be used against the poor than the rich, against a foreigner than an Indonesian citizen. Widodo's credibility in the matter has been shaken still further by his own efforts to save an Indonesian citizen from execution in Saudi Arabia. Clearly, he only supports the death penalty if it furthers his own political agenda.

The sense of revulsion about what has happened in Indonesia today will last for years. And the political opposition in Indonesia will be delighted by the mess Widodo has got himself into. He has played into their hands by damaging his own reputation and that of his country internationally. As a consequence, the political fallout vis-a-vis Indonesia's international partners, especially Australia, Brazil and Nigeria, the countries from where those now executed came, is immense. Some ambassadors have already been withdrawn and more will follow. Without doubt the executions will cause a serious diplomatic rift with Australia, which has left no stone unturned in a bid to win clemency for its citizens.

Nothing can console the families of those executed today. But we can all draw a tiny amount of comfort from the remarkable aspect of the wave of opposition to Joko Widodo's obsession with the death penalty for drugs crimes. As in the case of the Arab Spring and the Green Revolution in Iran, social media campaigns like #IStandForMercy, #Bali9 and #MaryJane have played a huge part in rallying support for the condemned and in generating intense opposition to the death penalty. It is to be hoped that the legacy of those executed on Wednesday will be that their case proves to be a turning point in the worldwide struggle against the death penalty.