The G20 committed a big mistake by naming as its chair for 2012 a possible war criminal who is in the midst of an intense electoral battle in his home country. Mexico's President Felipe Calderón will not push the G20 mandate of "promoting open and constructive discussion … on key issues related to global economic stability". His only interest will be to use this international forum for political purposes. In the context of widespread protest against global financial management, with Calderón at the helm, the G20 exposes itself to even greater popular anger.

Calderón has already convinced the G20 to move up its 2012 meeting in Los Cabos, Mexico, so that it takes place only a few weeks before the 1 July presidential elections. The Mexican president hopes to use the presence of the international leaders to boost his failing credibility and overcome his party's weakness in the polls. But precisely the opposite could be the case, since the highly-charged political environment in Mexico might lead to new social protests against the world leaders.

Calderón is particularly desperate for international recognition because on 25 November 2011, a group of lawyers, journalists, activists and academics, let by human rights lawyer Netzaí Sandoval, will bring a formal petition to the International Criminal Court (ICC) to investigate Calderón for war crimes and crimes against humanity. The petition is directed against the Mexican president and other top officials, as well as the leaders of Mexico's most important drug cartels, for refusing to follow the basic protocols that should rule armed conflicts and conducting systematic assault on the civilian population. The petition now has the support of almost 20,000 signatures online, as well as another 5-10,000 on paper.

Over the past five years, Calderón has presided over a bloodbath of historic proportions, with over 50,000 violent deaths (including at least 1,300 youth and children), 230,000 displaced people and at least 10,000 "disappeared" persons. This violence is not a normal outcome of the global economic downturn or of disputes between rival drug gangs, but indicates the existence of a full-blown humanitarian crisis. Indeed, the scale of the crisis is much larger than those in Congo, Sudan, Kenya or the Ivory Cost, all of which are presently under investigation by the ICC.

Calderón blames this situation on the drug cartels, but he may also be directly responsible. The upsurge in violence coincides with his rise to power on 1 December 2006, and there are no signs that organised crime has been weakened over the past five years. To the contrary, the cultivation and use of drugs in Mexico has risen dramatically, organised crime groups now have more firepower than ever before, money is freely laundered in the country and the impunity rate has reached an historic high (pdf), with, at most, 5% of all crimes actually receiving punishment. The idea that Calderón has conducted a "frontal attack" against organised crime is therefore patently false.

There is widespread suspicion, in fact, of complicity between Mexico's federal government and some of the cartels, including one of the most powerful drug bosses in the country, Joaquín "El Chapo" Guzmán. This hypothesis is supported by information from leading international news sources, such as National Public Radio, and is a common theme in most international reporting. It is hard to explain how else, in the middle of an all-out "war" against drugs, Guzmán has systematically climbed in the Forbes magazine wealth and power rankings to reach the status of 55th "most powerful person" in the world in 2011.

Regardless of these allegations, it is clear that the more than 40,000 soldiers who today occupy Mexico's streets under Calderón's command are not exclusively dedicated to keeping the peace. The military is trained to kill, and they have done so on hundreds, if not thousands, of occasions over the past five years while serving in the "drug war". Extra-judicial killings have become standard operating procedure and the military has been known to mutilate the bodies of its victims, in clear violation of the Rome Statute. Many of the killings occur in "self-defense" in response to criminal attacks, but a great many also take place at the initiative of the soldiers.

Innocent civilians are often directly targeted by the military for their "suspicious behavior". In general, human rights abuses and attacks against journalists have skyrocketed in recent years. The UN, the Inter-American Court for Human Rights, Amnesty International, Human Rights Watch, Mexico's Human Rights Commission and dozens of local NGOs time and again issue decisions and reports about the grave situation in Mexico – and the particularly worrisome role played by the military.

Instead of addressing these issues, Calderón brushes them off by stating that 90% of the dead are supposedly "linked" to organised crime. The implication is obvious: they deserved to die. Such callous disregard for the rule of law implies that the real approach to combating crime may actually be one of "social cleansing", in which unwanted elements of society are encouraged to kill each other off. The emergence of a new paramilitary group in southern Mexico, which has pledged its alliance to the military, but vowed to take the law into its own hands by killing members of a rival drug gang, may indicate the consolidation of this strategy.

In a recent visit to Mexico, the ICC's chief prosecutor, Luis Moreno Ocampo, has tried to minimise the allegations against Calderón by stating that the ICC does not judge "political decisions" or "political responsibility". Such pre-judgement of the case by the person responsible for any investigation is irresponsible to say the least, since the petition has not even been presented yet. It is also misdirected, since the petitioners by no means plan to accuse Calderón on the basis of his policy decisions, but for his direct responsibility as commander-in-chief of the armed forces.

Mexicans are tired of living in a land of impunity and have decided to begin their struggle for justice at the top, by holding to account the country's top public servant. The ICC will eventually have to investigate and decide on the merits of the case. Meanwhile, the G20 sends an ominous sign by honoring the man who has presided over so much carnage and reckless disregard for human rights in his country.