This week, Nigeria 'celebrates' the grim anniversary of ten years under investigation by the International Criminal Court (ICC). For such a hopeful and energetic nation, which promises so much to Africa and the world, this is no small landmark.

The global Court is probing crimes against humanity and war crimes by Boko Haram, a notorious Islamist faction dominating the north east and Middle Belt of the country, and Nigeria's own security forces. That the very force meant to defend innocent citizens is being scrutinised is a major red flag.

The ICC's job is to try the world's worst international crimes such as genocide, crimes against humanity, war crimes and aggression. It has opened twelve investigations, the highest form of scrutiny. Nigeria is at the next level down, where preliminary examinations are being carried out.

Yet this week marks Nigeria's tenth consecutive year on the case 'waiting list'. One has to wonder how long the actual investigations will take if the preliminary inquiry reaches a decade with little to show for it.

Fresh ICON evidence suggests 100,000 Nigerians have been killed by the Islamic State, Boko Haram or militant Fulani herdsmen since the year 2000, with all three groups heavily controlling the north east and Middle Belt of the country.

During this time period, deaths resulting from militant Fulani attacks include 17,284 across Nigeria and 13,079 in predominantly Christian states such as Benue, Kaduna, Plateau, and Taraba. That means three of every four militant Fulani victims during this time were Christians, not incidental by any means when reviewing genocide allegations.

On 4 July 2018, the Nigerian House of Representatives declared killings in predominantly Christian villages in Plateau State to be a genocide, requesting that the Federal Government immediately establish orphanages in areas affected by violence. If there is a genocide, as admitted by Nigeria's own legislature, then surely there must be a perpetrator to bring to justice.

This is one reason why I supported human rights charity PSJ UK's recent letter to the ICC, criticising them for their delay and recommending a swift resolution. The country needs to move on quickly, and build the foundations for a brighter future.

A ComRes poll commissioned by PSJ UK found international groups such as the UN, as well as the Nigerian government, are the bodies seen as most likely to speak out (49 per cent each) and take action (44 per cent and 51 per cent, respectively) against growing violence towards Christians in Nigeria.

The International Criminal Court cannot delay justice on the sanctioning and penalising of high-profile violators of human rights in fragile democracies such as Nigeria. It is a country with great potential, but in urgent need of transparency and accountability.

It would be a disservice to the people of Nigeria, Africa as a whole, and the principle of justice to overlook or dismiss alleged crimes by Boko Haram, and by the Nigerian military. The world is watching, with the ICC's legitimacy very much at stake.

For the sake of Nigeria, but also global trust in the international legal system, I hope another tragic anniversary in the ICC's dusty records will be the last one Nigeria's silenced population has to suffer.

Paul Diamond is a leading religious and human rights barrister and standing counsel to the Christian Legal Centre.