Even the most adamant supporters of the war on drugs agree that it is failing. At a major UN summit on drug policy earlier this year, many member states argued forcefully for a more balanced and humane approach. But there’s one anti-drug crusader who refuses to face the facts. For the past six months Rodrigo Duterte, president of the Philippines has waged one of the world’s most vicious counter-narcotics campaigns.

Duterte campaigned for president with a pledge to clean up the drug menace for good. Within days of winning the election he launched a scorched earth approach targeting anyone suspected of being involved in consuming or selling narcotics. During his inaugural address on 30 June, the one-time mayor of Davao city vowed to “slaughter these idiots for destroying my country”.

And kill them he has. The national police estimates that more than 6,000 people were assassinated by law enforcement, paramilitaries and vigilantes since 1 July 2016. The police say that at least 2,000 people were shot and killed by officers in “self defence” during anti-drug operations. Around 33 people are killed for every one person injured, making this the most deadly drug war ever. Another 38,000 people have reportedly been jailed, fuelling a crisis in the country’s overpopulated prisons.

The president exults in the bloodbath. He recently boasted of killing suspects during his time as mayor, saying in “Davao I used to do it personally”, suggesting that summary executions are tolerated at the very top.

The president claims to have “cleaned up the streets” of Davao during his roughly two decades in power, calling it one of the world’s safest cities. Although the city is certainly cleaner and features new legislation that improves crime reporting, claims of public safety are vastly overstated. Indeed, publicly available data on crime shows the city posted the highest rates of murder and second highest rates of rape in the country between 2010-2015.

Inmates in an overcrowded police jail cell in Manila, Philippines. Photograph: Dondi Tawatao/Getty Images

Duterte has a nasty habit of playing fast and loose with the facts. In a bid to give credence to his drug war, his team exaggerates and invents data. For example, Duterte inflated the estimated number of drug users in the country, stating that there are currently 4 million users – with as many as 10 million projected by 2020. Yet the country’s own drug authorities contend that the number of users of hard drugs is much lower. The prevalence rate for drug use by Filipinos is actually closer to 2.3% (pdf), roughly half the global average. Inflammatory rhetoric and dodgy data have real world consequences. Not only can they incite violence, but they also determine the shape of government policy.

Yet Duterte’s tough on crime bombast goes down well with Filipinos. His use of Visayan slang (rather than just Tagalog or English) marks him as one of the people, and his approval ratings are topping 85%, though this is typical for first year presidents. Nevertheless, there are signs that the opposition is beginning to rally, with some senators calling for his impeachment. His authoritarian tendencies are also starting to worry civil liberties experts: at a press conference he responded to one question by saying “just because you’re a journalist you are not exempted from assassination”, and last month he threatened to kill human rights activists because of their criticism of his crackdown on crime.

Duterte is upending the country’s international image. On the one hand, he has undermined the prospect of a serious and evidence-based strategy to prevent drug abuse problems, including of “shabu”, a highly addictive methamphetamine with dangerous side effects. His dragnet collapses users of a wide range of drugs with devastating effect, including violating basic human rights. This kind of impunity cannot be tolerated.

It may be time to consider divesting from companies that are directly and indirectly fuelling the massacre of Filipinos

But foreign governments are noticeably quiet about Duterte’s bloody campaign. The White House recently condemned statements by the president but is reluctant to take action for fear of jeopardising the visiting forces agreement and other geo-strategic priorities in the region. For his part, US president-elect Trump speaks admiringly of Duterte’s antics. In addition to cozying up with China, Duterte recently threatened to withdraw from the UN in response to criticism of his drug war. Soon after, the UN special rapporteur on extrajudicial killings cancelled a visit to the country after the president imposed unprecedented conditions on her visit.

There are signs that human rights specialists are beginning to fight back. Religious and civil society groups are already mobilising to push back against the state-sanctioned killings. The Philippines former secretary of justice and chair of the Commission on Human Rights, Leila de Lima, is one of the president’s most vocal critics. Outside of the Philippines, the UN special rapporteur on the right to health called for drug dependency to be treated as a public health issue and the decriminalisation of consumption. What’s more, the 18-member UN committee on economic, social and cultural rights took Duterte to task for the massacre of suspects.

Bolder action is needed. The international criminal court could start by treating the situation in the Philippines as a “crime against humanity” and opening an investigation. The chief prosecutor has already expressed she is “deeply concerned” about the violent crackdown on drug users and suspected dealers. The president responded with characteristic bravado, describing foreign lawyers as “idiots” and the threats as “bullshit”. The UN security council can also refer the situation to the ICC in order to investigate the president and other senior officials involved in the killing.

The international community can also consider economic sanctions. Duterte has told worried businesses to “pack up and leave”, claiming that the Chinese would happily take their place. Perhaps foreign businesses should take his advice. The European, American and Nordic Chambers of Commerce would do well to revisit the compatibility of their investments and shareholder concerns with systemic violations of human rights. It may be time to consider divesting from companies that are directly and indirectly fuelling the massacre of Filipinos.

Foreign governments should also consider withdrawing their aid to the Philippines if no change of direction materialises. The US started taking steps in this direction. After voicing their alarm with the president’s alleged involvement in assassinations, the US Millennium Challenge Corp deferred renewal of a poverty reduction programme “subject to a further review of concerns around the rule of law and civil liberties”. An earlier $434m (£353m) dollar package expired the month before Duterte’s taking office. Other aid agencies should follow suit. Duterte will no doubt brush it off, but it’s time to show that short-term financial imperatives should not trump human rights.

Robert Muggah is research director of the Igarapé Institute and SecDev Foundation.

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